whiterose

linux unikernel
Log | Files | Refs | README | LICENSE | git clone https://git.ne02ptzero.me/git/whiterose

commit f47d633134f7033e3d0c667419d9f8afd69e308d
parent 004cc08675b761fd82288bab1b5ba5e1ca746eca
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 12 Mar 2019 09:46:32 -0700

Merge tag 'tag-chrome-platform-for-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux

Pull chrome platform updates from Benson Leung:

 - SPDX identifier cleanup for platform/chrome

 - Cleanup series between mfd and chrome/platform, moving cros-ec
   attributes from mfd/cros_ec_dev to sub-drivers in platform/chrome

 - Wilco EC driver

 - Maintainership change to new group repository

* tag 'tag-chrome-platform-for-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux:
  platform/chrome: fix wilco-ec dependencies
  platform/chrome: wilco_ec: Add RTC driver
  platform/chrome: wilco_ec: Add support for raw commands in debugfs
  platform/chrome: Add new driver for Wilco EC
  platform/chrome: cros_ec: Remove cros_ec dependency in lpc_mec
  MAINTAINERS: chrome-platform: change the git tree to a chrome-platform group git tree
  platform/chrome: cros_ec_sysfs: remove pr_fmt() define
  platform/chrome: cros_ec_lightbar: remove pr_fmt() define
  platform/chrome: cros_kbd_led_backlight: switch to SPDX identifier
  platform/chrome: cros_ec_spi: switch to SPDX identifier
  platform/chrome: cros_ec_proto: switch to SPDX identifier
  platform/chrome: cros_ec_lpc: switch to SPDX identifier
  platform/chrome: cros_ec_i2c: switch to SPDX identifier
  platform/chrome: cros_ec_vbc: switch to SPDX identifier
  platform/chrome: cros_ec_sysfs: switch to SPDX identifier
  platform/chrome: cros_ec_lightbar: switch to SPDX identifier
  platform/chrome: cros_ec_debugfs: switch to SPDX identifier
  platform/chrome: cromeos_pstore: switch to SPDX identifier

Diffstat:
ADocumentation/ABI/testing/debugfs-wilco-ec | 23+++++++++++++++++++++++
MMAINTAINERS | 2+-
Mdrivers/platform/chrome/Kconfig | 2++
Mdrivers/platform/chrome/Makefile | 2++
Mdrivers/platform/chrome/chromeos_pstore.c | 17++++++-----------
Mdrivers/platform/chrome/cros_ec_debugfs.c | 22++++------------------
Mdrivers/platform/chrome/cros_ec_i2c.c | 22++++++----------------
Mdrivers/platform/chrome/cros_ec_lightbar.c | 24++++--------------------
Mdrivers/platform/chrome/cros_ec_lpc.c | 34++++++++++++----------------------
Mdrivers/platform/chrome/cros_ec_lpc_mec.c | 78+++++++++++++++++++++++++++++++++++++++++++++++-------------------------------
Mdrivers/platform/chrome/cros_ec_lpc_mec.h | 63++++++++++++++++++++++++++-------------------------------------
Mdrivers/platform/chrome/cros_ec_lpc_reg.c | 73++++++++++++++++++++-----------------------------------------------------
Mdrivers/platform/chrome/cros_ec_lpc_reg.h | 20++------------------
Mdrivers/platform/chrome/cros_ec_proto.c | 19++++---------------
Mdrivers/platform/chrome/cros_ec_spi.c | 20+++++---------------
Mdrivers/platform/chrome/cros_ec_sysfs.c | 26+++++---------------------
Mdrivers/platform/chrome/cros_ec_vbc.c | 24+++++-------------------
Mdrivers/platform/chrome/cros_kbd_led_backlight.c | 19++++---------------
Adrivers/platform/chrome/wilco_ec/Kconfig | 20++++++++++++++++++++
Adrivers/platform/chrome/wilco_ec/Makefile | 6++++++
Adrivers/platform/chrome/wilco_ec/core.c | 136+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Adrivers/platform/chrome/wilco_ec/debugfs.c | 238+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Adrivers/platform/chrome/wilco_ec/mailbox.c | 237+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Mdrivers/rtc/Kconfig | 11+++++++++++
Mdrivers/rtc/Makefile | 1+
Adrivers/rtc/rtc-wilco-ec.c | 177+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Ainclude/linux/platform_data/wilco-ec.h | 144+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
27 files changed, 1148 insertions(+), 312 deletions(-)

diff --git a/Documentation/ABI/testing/debugfs-wilco-ec b/Documentation/ABI/testing/debugfs-wilco-ec @@ -0,0 +1,23 @@ +What: /sys/kernel/debug/wilco_ec/raw +Date: January 2019 +KernelVersion: 5.1 +Description: + Write and read raw mailbox commands to the EC. + + For writing: + Bytes 0-1 indicate the message type: + 00 F0 = Execute Legacy Command + 00 F2 = Read/Write NVRAM Property + Byte 2 provides the command code + Bytes 3+ consist of the data passed in the request + + At least three bytes are required, for the msg type and command, + with additional bytes optional for additional data. + + Example: + // Request EC info type 3 (EC firmware build date) + $ echo 00 f0 38 00 03 00 > raw + // View the result. The decoded ASCII result "12/21/18" is + // included after the raw hex. + $ cat raw + 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 .12/21/18.8... diff --git a/MAINTAINERS b/MAINTAINERS @@ -3755,7 +3755,7 @@ CHROME HARDWARE PLATFORM SUPPORT M: Benson Leung <bleung@chromium.org> M: Enric Balletbo i Serra <enric.balletbo@collabora.com> S: Maintained -T: git git://git.kernel.org/pub/scm/linux/kernel/git/bleung/chrome-platform.git +T: git git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git F: drivers/platform/chrome/ CHROMEOS EC SUBDRIVERS diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig @@ -152,4 +152,6 @@ config CROS_EC_SYSFS To compile this driver as a module, choose M here: the module will be called cros_ec_sysfs. +source "drivers/platform/chrome/wilco_ec/Kconfig" + endif # CHROMEOS_PLATFORMS diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile @@ -14,3 +14,5 @@ obj-$(CONFIG_CROS_EC_LIGHTBAR) += cros_ec_lightbar.o obj-$(CONFIG_CROS_EC_VBC) += cros_ec_vbc.o obj-$(CONFIG_CROS_EC_DEBUGFS) += cros_ec_debugfs.o obj-$(CONFIG_CROS_EC_SYSFS) += cros_ec_sysfs.o + +obj-$(CONFIG_WILCO_EC) += wilco_ec/ diff --git a/drivers/platform/chrome/chromeos_pstore.c b/drivers/platform/chrome/chromeos_pstore.c @@ -1,12 +1,7 @@ -/* - * chromeos_pstore.c - Driver to instantiate Chromebook ramoops device - * - * Copyright (C) 2013 Google, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation, version 2 of the License. - */ +// SPDX-License-Identifier: GPL-2.0 +// Driver to instantiate Chromebook ramoops device. +// +// Copyright (C) 2013 Google, Inc. #include <linux/acpi.h> #include <linux/dmi.h> @@ -138,5 +133,5 @@ static void __exit chromeos_pstore_exit(void) module_init(chromeos_pstore_init); module_exit(chromeos_pstore_exit); -MODULE_DESCRIPTION("Chrome OS pstore module"); -MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("ChromeOS pstore module"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c @@ -1,21 +1,7 @@ -/* - * cros_ec_debugfs - debug logs for Chrome OS EC - * - * Copyright 2015 Google, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ +// SPDX-License-Identifier: GPL-2.0+ +// Debug logs for the ChromeOS EC +// +// Copyright (C) 2015 Google, Inc. #include <linux/circ_buf.h> #include <linux/debugfs.h> diff --git a/drivers/platform/chrome/cros_ec_i2c.c b/drivers/platform/chrome/cros_ec_i2c.c @@ -1,17 +1,7 @@ -/* - * ChromeOS EC multi-function device (I2C) - * - * Copyright (C) 2012 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ +// SPDX-License-Identifier: GPL-2.0 +// I2C interface for ChromeOS Embedded Controller +// +// Copyright (C) 2012 Google, Inc #include <linux/acpi.h> #include <linux/delay.h> @@ -372,5 +362,5 @@ static struct i2c_driver cros_ec_driver = { module_i2c_driver(cros_ec_driver); -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("ChromeOS EC multi function device"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("I2C interface for ChromeOS Embedded Controller"); diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c @@ -1,23 +1,7 @@ -/* - * cros_ec_lightbar - expose the Chromebook Pixel lightbar to userspace - * - * Copyright (C) 2014 Google, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#define pr_fmt(fmt) "cros_ec_lightbar: " fmt +// SPDX-License-Identifier: GPL-2.0+ +// Expose the Chromebook Pixel lightbar to userspace +// +// Copyright (C) 2014 Google, Inc. #include <linux/ctype.h> #include <linux/delay.h> diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c @@ -1,25 +1,15 @@ -/* - * cros_ec_lpc - LPC access to the Chrome OS Embedded Controller - * - * Copyright (C) 2012-2015 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * This driver uses the Chrome OS EC byte-level message-based protocol for - * communicating the keyboard state (which keys are pressed) from a keyboard EC - * to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing, - * but everything else (including deghosting) is done here. The main - * motivation for this is to keep the EC firmware as simple as possible, since - * it cannot be easily upgraded and EC flash/IRAM space is relatively - * expensive. - */ +// SPDX-License-Identifier: GPL-2.0 +// LPC interface for ChromeOS Embedded Controller +// +// Copyright (C) 2012-2015 Google, Inc +// +// This driver uses the ChromeOS EC byte-level message-based protocol for +// communicating the keyboard state (which keys are pressed) from a keyboard EC +// to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing, +// but everything else (including deghosting) is done here. The main +// motivation for this is to keep the EC firmware as simple as possible, since +// it cannot be easily upgraded and EC flash/IRAM space is relatively +// expensive. #include <linux/acpi.h> #include <linux/dmi.h> diff --git a/drivers/platform/chrome/cros_ec_lpc_mec.c b/drivers/platform/chrome/cros_ec_lpc_mec.c @@ -1,29 +1,10 @@ -/* - * cros_ec_lpc_mec - LPC variant I/O for Microchip EC - * - * Copyright (C) 2016 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * This driver uses the Chrome OS EC byte-level message-based protocol for - * communicating the keyboard state (which keys are pressed) from a keyboard EC - * to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing, - * but everything else (including deghosting) is done here. The main - * motivation for this is to keep the EC firmware as simple as possible, since - * it cannot be easily upgraded and EC flash/IRAM space is relatively - * expensive. - */ +// SPDX-License-Identifier: GPL-2.0 +// LPC variant I/O for Microchip EC +// +// Copyright (C) 2016 Google, Inc #include <linux/delay.h> #include <linux/io.h> -#include <linux/mfd/cros_ec_commands.h> #include <linux/mutex.h> #include <linux/types.h> @@ -34,6 +15,7 @@ * EC mutex because memmap data may be accessed without it being held. */ static struct mutex io_mutex; +static u16 mec_emi_base, mec_emi_end; /* * cros_ec_lpc_mec_emi_write_address @@ -46,10 +28,37 @@ static struct mutex io_mutex; static void cros_ec_lpc_mec_emi_write_address(u16 addr, enum cros_ec_lpc_mec_emi_access_mode access_type) { - /* Address relative to start of EMI range */ - addr -= MEC_EMI_RANGE_START; - outb((addr & 0xfc) | access_type, MEC_EMI_EC_ADDRESS_B0); - outb((addr >> 8) & 0x7f, MEC_EMI_EC_ADDRESS_B1); + outb((addr & 0xfc) | access_type, MEC_EMI_EC_ADDRESS_B0(mec_emi_base)); + outb((addr >> 8) & 0x7f, MEC_EMI_EC_ADDRESS_B1(mec_emi_base)); +} + +/** + * cros_ec_lpc_mec_in_range() - Determine if addresses are in MEC EMI range. + * + * @offset: Address offset + * @length: Number of bytes to check + * + * Return: 1 if in range, 0 if not, and -EINVAL on failure + * such as the mec range not being initialized + */ +int cros_ec_lpc_mec_in_range(unsigned int offset, unsigned int length) +{ + if (length == 0) + return -EINVAL; + + if (WARN_ON(mec_emi_base == 0 || mec_emi_end == 0)) + return -EINVAL; + + if (offset >= mec_emi_base && offset < mec_emi_end) { + if (WARN_ON(offset + length - 1 >= mec_emi_end)) + return -EINVAL; + return 1; + } + + if (WARN_ON(offset + length > mec_emi_base && offset < mec_emi_end)) + return -EINVAL; + + return 0; } /* @@ -71,6 +80,11 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type, u8 sum = 0; enum cros_ec_lpc_mec_emi_access_mode access, new_access; + /* Return checksum of 0 if window is not initialized */ + WARN_ON(mec_emi_base == 0 || mec_emi_end == 0); + if (mec_emi_base == 0 || mec_emi_end == 0) + return 0; + /* * Long access cannot be used on misaligned data since reading B0 loads * the data register and writing B3 flushes. @@ -86,9 +100,9 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type, cros_ec_lpc_mec_emi_write_address(offset, access); /* Skip bytes in case of misaligned offset */ - io_addr = MEC_EMI_EC_DATA_B0 + (offset & 0x3); + io_addr = MEC_EMI_EC_DATA_B0(mec_emi_base) + (offset & 0x3); while (i < length) { - while (io_addr <= MEC_EMI_EC_DATA_B3) { + while (io_addr <= MEC_EMI_EC_DATA_B3(mec_emi_base)) { if (io_type == MEC_IO_READ) buf[i] = inb(io_addr++); else @@ -118,7 +132,7 @@ u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type, } /* Access [B0, B3] on each loop pass */ - io_addr = MEC_EMI_EC_DATA_B0; + io_addr = MEC_EMI_EC_DATA_B0(mec_emi_base); } done: @@ -128,9 +142,11 @@ done: } EXPORT_SYMBOL(cros_ec_lpc_io_bytes_mec); -void cros_ec_lpc_mec_init(void) +void cros_ec_lpc_mec_init(unsigned int base, unsigned int end) { mutex_init(&io_mutex); + mec_emi_base = base; + mec_emi_end = end; } EXPORT_SYMBOL(cros_ec_lpc_mec_init); diff --git a/drivers/platform/chrome/cros_ec_lpc_mec.h b/drivers/platform/chrome/cros_ec_lpc_mec.h @@ -1,31 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ /* - * cros_ec_lpc_mec - LPC variant I/O for Microchip EC + * LPC variant I/O for Microchip EC * * Copyright (C) 2016 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * This driver uses the Chrome OS EC byte-level message-based protocol for - * communicating the keyboard state (which keys are pressed) from a keyboard EC - * to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing, - * but everything else (including deghosting) is done here. The main - * motivation for this is to keep the EC firmware as simple as possible, since - * it cannot be easily upgraded and EC flash/IRAM space is relatively - * expensive. */ #ifndef __CROS_EC_LPC_MEC_H #define __CROS_EC_LPC_MEC_H -#include <linux/mfd/cros_ec_commands.h> - enum cros_ec_lpc_mec_emi_access_mode { /* 8-bit access */ ACCESS_TYPE_BYTE = 0x0, @@ -45,27 +27,23 @@ enum cros_ec_lpc_mec_io_type { MEC_IO_WRITE, }; -/* Access IO ranges 0x800 thru 0x9ff using EMI interface instead of LPC */ -#define MEC_EMI_RANGE_START EC_HOST_CMD_REGION0 -#define MEC_EMI_RANGE_END (EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE) - /* EMI registers are relative to base */ -#define MEC_EMI_BASE 0x800 -#define MEC_EMI_HOST_TO_EC (MEC_EMI_BASE + 0) -#define MEC_EMI_EC_TO_HOST (MEC_EMI_BASE + 1) -#define MEC_EMI_EC_ADDRESS_B0 (MEC_EMI_BASE + 2) -#define MEC_EMI_EC_ADDRESS_B1 (MEC_EMI_BASE + 3) -#define MEC_EMI_EC_DATA_B0 (MEC_EMI_BASE + 4) -#define MEC_EMI_EC_DATA_B1 (MEC_EMI_BASE + 5) -#define MEC_EMI_EC_DATA_B2 (MEC_EMI_BASE + 6) -#define MEC_EMI_EC_DATA_B3 (MEC_EMI_BASE + 7) +#define MEC_EMI_HOST_TO_EC(MEC_EMI_BASE) ((MEC_EMI_BASE) + 0) +#define MEC_EMI_EC_TO_HOST(MEC_EMI_BASE) ((MEC_EMI_BASE) + 1) +#define MEC_EMI_EC_ADDRESS_B0(MEC_EMI_BASE) ((MEC_EMI_BASE) + 2) +#define MEC_EMI_EC_ADDRESS_B1(MEC_EMI_BASE) ((MEC_EMI_BASE) + 3) +#define MEC_EMI_EC_DATA_B0(MEC_EMI_BASE) ((MEC_EMI_BASE) + 4) +#define MEC_EMI_EC_DATA_B1(MEC_EMI_BASE) ((MEC_EMI_BASE) + 5) +#define MEC_EMI_EC_DATA_B2(MEC_EMI_BASE) ((MEC_EMI_BASE) + 6) +#define MEC_EMI_EC_DATA_B3(MEC_EMI_BASE) ((MEC_EMI_BASE) + 7) -/* - * cros_ec_lpc_mec_init +/** + * cros_ec_lpc_mec_init() - Initialize MEC I/O. * - * Initialize MEC I/O. + * @base: MEC EMI Base address + * @end: MEC EMI End address */ -void cros_ec_lpc_mec_init(void); +void cros_ec_lpc_mec_init(unsigned int base, unsigned int end); /* * cros_ec_lpc_mec_destroy @@ -75,6 +53,17 @@ void cros_ec_lpc_mec_init(void); void cros_ec_lpc_mec_destroy(void); /** + * cros_ec_lpc_mec_in_range() - Determine if addresses are in MEC EMI range. + * + * @offset: Address offset + * @length: Number of bytes to check + * + * Return: 1 if in range, 0 if not, and -EINVAL on failure + * such as the mec range not being initialized + */ +int cros_ec_lpc_mec_in_range(unsigned int offset, unsigned int length); + +/** * cros_ec_lpc_io_bytes_mec - Read / write bytes to MEC EMI port * * @io_type: MEC_IO_READ or MEC_IO_WRITE, depending on request diff --git a/drivers/platform/chrome/cros_ec_lpc_reg.c b/drivers/platform/chrome/cros_ec_lpc_reg.c @@ -1,25 +1,7 @@ -/* - * cros_ec_lpc_reg - LPC access to the Chrome OS Embedded Controller - * - * Copyright (C) 2016 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * This driver uses the Chrome OS EC byte-level message-based protocol for - * communicating the keyboard state (which keys are pressed) from a keyboard EC - * to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing, - * but everything else (including deghosting) is done here. The main - * motivation for this is to keep the EC firmware as simple as possible, since - * it cannot be easily upgraded and EC flash/IRAM space is relatively - * expensive. - */ +// SPDX-License-Identifier: GPL-2.0 +// LPC interface for ChromeOS Embedded Controller +// +// Copyright (C) 2016 Google, Inc #include <linux/io.h> #include <linux/mfd/cros_ec.h> @@ -59,51 +41,36 @@ static u8 lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg) u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest) { - if (length == 0) - return 0; - - /* Access desired range through EMI interface */ - if (offset >= MEC_EMI_RANGE_START && offset <= MEC_EMI_RANGE_END) { - /* Ensure we don't straddle EMI region */ - if (WARN_ON(offset + length - 1 > MEC_EMI_RANGE_END)) - return 0; + int in_range = cros_ec_lpc_mec_in_range(offset, length); - return cros_ec_lpc_io_bytes_mec(MEC_IO_READ, offset, length, - dest); - } - - if (WARN_ON(offset + length > MEC_EMI_RANGE_START && - offset < MEC_EMI_RANGE_START)) + if (in_range < 0) return 0; - return lpc_read_bytes(offset, length, dest); + return in_range ? + cros_ec_lpc_io_bytes_mec(MEC_IO_READ, + offset - EC_HOST_CMD_REGION0, + length, dest) : + lpc_read_bytes(offset, length, dest); } u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg) { - if (length == 0) - return 0; - - /* Access desired range through EMI interface */ - if (offset >= MEC_EMI_RANGE_START && offset <= MEC_EMI_RANGE_END) { - /* Ensure we don't straddle EMI region */ - if (WARN_ON(offset + length - 1 > MEC_EMI_RANGE_END)) - return 0; + int in_range = cros_ec_lpc_mec_in_range(offset, length); - return cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, offset, length, - msg); - } - - if (WARN_ON(offset + length > MEC_EMI_RANGE_START && - offset < MEC_EMI_RANGE_START)) + if (in_range < 0) return 0; - return lpc_write_bytes(offset, length, msg); + return in_range ? + cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, + offset - EC_HOST_CMD_REGION0, + length, msg) : + lpc_write_bytes(offset, length, msg); } void cros_ec_lpc_reg_init(void) { - cros_ec_lpc_mec_init(); + cros_ec_lpc_mec_init(EC_HOST_CMD_REGION0, + EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE); } void cros_ec_lpc_reg_destroy(void) diff --git a/drivers/platform/chrome/cros_ec_lpc_reg.h b/drivers/platform/chrome/cros_ec_lpc_reg.h @@ -1,24 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0 */ /* - * cros_ec_lpc_reg - LPC access to the Chrome OS Embedded Controller + * LPC interface for ChromeOS Embedded Controller * * Copyright (C) 2016 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * This driver uses the Chrome OS EC byte-level message-based protocol for - * communicating the keyboard state (which keys are pressed) from a keyboard EC - * to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing, - * but everything else (including deghosting) is done here. The main - * motivation for this is to keep the EC firmware as simple as possible, since - * it cannot be easily upgraded and EC flash/IRAM space is relatively - * expensive. */ #ifndef __CROS_EC_LPC_REG_H diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c @@ -1,18 +1,7 @@ -/* - * ChromeOS EC communication protocol helper functions - * - * Copyright (C) 2015 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - */ +// SPDX-License-Identifier: GPL-2.0 +// ChromeOS EC communication protocol helper functions +// +// Copyright (C) 2015 Google, Inc #include <linux/mfd/cros_ec.h> #include <linux/delay.h> diff --git a/drivers/platform/chrome/cros_ec_spi.c b/drivers/platform/chrome/cros_ec_spi.c @@ -1,17 +1,7 @@ -/* - * ChromeOS EC multi-function device (SPI) - * - * Copyright (C) 2012 Google, Inc - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ +// SPDX-License-Identifier: GPL-2.0 +// SPI interface for ChromeOS Embedded Controller +// +// Copyright (C) 2012 Google, Inc #include <linux/delay.h> #include <linux/kernel.h> @@ -729,4 +719,4 @@ static struct spi_driver cros_ec_driver_spi = { module_spi_driver(cros_ec_driver_spi); MODULE_LICENSE("GPL v2"); -MODULE_DESCRIPTION("ChromeOS EC multi function device (SPI)"); +MODULE_DESCRIPTION("SPI interface for ChromeOS Embedded Controller"); diff --git a/drivers/platform/chrome/cros_ec_sysfs.c b/drivers/platform/chrome/cros_ec_sysfs.c @@ -1,23 +1,7 @@ -/* - * cros_ec_sysfs - expose the Chrome OS EC through sysfs - * - * Copyright (C) 2014 Google, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#define pr_fmt(fmt) "cros_ec_sysfs: " fmt +// SPDX-License-Identifier: GPL-2.0+ +// Expose the ChromeOS EC through sysfs +// +// Copyright (C) 2014 Google, Inc. #include <linux/ctype.h> #include <linux/delay.h> @@ -389,5 +373,5 @@ static struct platform_driver cros_ec_sysfs_driver = { module_platform_driver(cros_ec_sysfs_driver); MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("ChromeOS EC control driver"); +MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs"); MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/platform/chrome/cros_ec_vbc.c b/drivers/platform/chrome/cros_ec_vbc.c @@ -1,22 +1,8 @@ -/* - * cros_ec_vbc - Expose the vboot context nvram to userspace - * - * Copyright (C) 2015 Collabora Ltd. - * - * based on vendor driver, - * - * Copyright (C) 2012 The Chromium OS Authors - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ +// SPDX-License-Identifier: GPL-2.0+ +// Expose the vboot context nvram to userspace +// +// Copyright (C) 2012 Google, Inc. +// Copyright (C) 2015 Collabora Ltd. #include <linux/of.h> #include <linux/platform_device.h> diff --git a/drivers/platform/chrome/cros_kbd_led_backlight.c b/drivers/platform/chrome/cros_kbd_led_backlight.c @@ -1,18 +1,7 @@ -/* - * Keyboard backlight LED driver for Chrome OS. - * - * Copyright (C) 2012 Google, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ +// SPDX-License-Identifier: GPL-2.0+ +// Keyboard backlight LED driver for ChromeOS +// +// Copyright (C) 2012 Google, Inc. #include <linux/acpi.h> #include <linux/leds.h> diff --git a/drivers/platform/chrome/wilco_ec/Kconfig b/drivers/platform/chrome/wilco_ec/Kconfig @@ -0,0 +1,20 @@ +config WILCO_EC + tristate "ChromeOS Wilco Embedded Controller" + depends on ACPI && X86 && CROS_EC_LPC && CROS_EC_LPC_MEC + help + If you say Y here, you get support for talking to the ChromeOS + Wilco EC over an eSPI bus. This uses a simple byte-level protocol + with a checksum. + + To compile this driver as a module, choose M here: the + module will be called wilco_ec. + +config WILCO_EC_DEBUGFS + tristate "Enable raw access to EC via debugfs" + depends on WILCO_EC + help + If you say Y here, you get support for sending raw commands to + the Wilco EC via debugfs. These commands do not do any byte + manipulation and allow for testing arbitrary commands. This + interface is intended for debug only and will not be present + on production devices. diff --git a/drivers/platform/chrome/wilco_ec/Makefile b/drivers/platform/chrome/wilco_ec/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 + +wilco_ec-objs := core.o mailbox.o +obj-$(CONFIG_WILCO_EC) += wilco_ec.o +wilco_ec_debugfs-objs := debugfs.o +obj-$(CONFIG_WILCO_EC_DEBUGFS) += wilco_ec_debugfs.o diff --git a/drivers/platform/chrome/wilco_ec/core.c b/drivers/platform/chrome/wilco_ec/core.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Core driver for Wilco Embedded Controller + * + * Copyright 2018 Google LLC + * + * This is the entry point for the drivers that control the Wilco EC. + * This driver is responsible for several tasks: + * - Initialize the register interface that is used by wilco_ec_mailbox() + * - Create a platform device which is picked up by the debugfs driver + * - Create a platform device which is picked up by the RTC driver + */ + +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/platform_device.h> + +#include "../cros_ec_lpc_mec.h" + +#define DRV_NAME "wilco-ec" + +static struct resource *wilco_get_resource(struct platform_device *pdev, + int index) +{ + struct device *dev = &pdev->dev; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_IO, index); + if (!res) { + dev_dbg(dev, "Couldn't find IO resource %d\n", index); + return res; + } + + return devm_request_region(dev, res->start, resource_size(res), + dev_name(dev)); +} + +static int wilco_ec_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct wilco_ec_device *ec; + int ret; + + ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL); + if (!ec) + return -ENOMEM; + + platform_set_drvdata(pdev, ec); + ec->dev = dev; + mutex_init(&ec->mailbox_lock); + + /* Largest data buffer size requirement is extended data response */ + ec->data_size = sizeof(struct wilco_ec_response) + + EC_MAILBOX_DATA_SIZE_EXTENDED; + ec->data_buffer = devm_kzalloc(dev, ec->data_size, GFP_KERNEL); + if (!ec->data_buffer) + return -ENOMEM; + + /* Prepare access to IO regions provided by ACPI */ + ec->io_data = wilco_get_resource(pdev, 0); /* Host Data */ + ec->io_command = wilco_get_resource(pdev, 1); /* Host Command */ + ec->io_packet = wilco_get_resource(pdev, 2); /* MEC EMI */ + if (!ec->io_data || !ec->io_command || !ec->io_packet) + return -ENODEV; + + /* Initialize cros_ec register interface for communication */ + cros_ec_lpc_mec_init(ec->io_packet->start, + ec->io_packet->start + EC_MAILBOX_DATA_SIZE); + + /* + * Register a child device that will be found by the debugfs driver. + * Ignore failure. + */ + ec->debugfs_pdev = platform_device_register_data(dev, + "wilco-ec-debugfs", + PLATFORM_DEVID_AUTO, + NULL, 0); + + /* Register a child device that will be found by the RTC driver. */ + ec->rtc_pdev = platform_device_register_data(dev, "rtc-wilco-ec", + PLATFORM_DEVID_AUTO, + NULL, 0); + if (IS_ERR(ec->rtc_pdev)) { + dev_err(dev, "Failed to create RTC platform device\n"); + ret = PTR_ERR(ec->rtc_pdev); + goto unregister_debugfs; + } + + return 0; + +unregister_debugfs: + if (ec->debugfs_pdev) + platform_device_unregister(ec->debugfs_pdev); + cros_ec_lpc_mec_destroy(); + return ret; +} + +static int wilco_ec_remove(struct platform_device *pdev) +{ + struct wilco_ec_device *ec = platform_get_drvdata(pdev); + + platform_device_unregister(ec->rtc_pdev); + if (ec->debugfs_pdev) + platform_device_unregister(ec->debugfs_pdev); + + /* Teardown cros_ec interface */ + cros_ec_lpc_mec_destroy(); + + return 0; +} + +static const struct acpi_device_id wilco_ec_acpi_device_ids[] = { + { "GOOG000C", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, wilco_ec_acpi_device_ids); + +static struct platform_driver wilco_ec_driver = { + .driver = { + .name = DRV_NAME, + .acpi_match_table = wilco_ec_acpi_device_ids, + }, + .probe = wilco_ec_probe, + .remove = wilco_ec_remove, +}; + +module_platform_driver(wilco_ec_driver); + +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_AUTHOR("Duncan Laurie <dlaurie@chromium.org>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("ChromeOS Wilco Embedded Controller driver"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/platform/chrome/wilco_ec/debugfs.c b/drivers/platform/chrome/wilco_ec/debugfs.c @@ -0,0 +1,238 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * debugfs attributes for Wilco EC + * + * Copyright 2019 Google LLC + * + * There is only one attribute used for debugging, called raw. + * You can write a hexadecimal sentence to raw, and that series of bytes + * will be sent to the EC. Then, you can read the bytes of response + * by reading from raw. + * + * For writing: + * Bytes 0-1 indicate the message type: + * 00 F0 = Execute Legacy Command + * 00 F2 = Read/Write NVRAM Property + * Byte 2 provides the command code + * Bytes 3+ consist of the data passed in the request + * + * When referencing the EC interface spec, byte 2 corresponds to MBOX[0], + * byte 3 corresponds to MBOX[1], etc. + * + * At least three bytes are required, for the msg type and command, + * with additional bytes optional for additional data. + * + * Example: + * // Request EC info type 3 (EC firmware build date) + * $ echo 00 f0 38 00 03 00 > raw + * // View the result. The decoded ASCII result "12/21/18" is + * // included after the raw hex. + * $ cat raw + * 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 .12/21/18.8... + */ + +#include <linux/ctype.h> +#include <linux/debugfs.h> +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/platform_device.h> + +#define DRV_NAME "wilco-ec-debugfs" + +/* The 256 raw bytes will take up more space when represented as a hex string */ +#define FORMATTED_BUFFER_SIZE (EC_MAILBOX_DATA_SIZE_EXTENDED * 4) + +struct wilco_ec_debugfs { + struct wilco_ec_device *ec; + struct dentry *dir; + size_t response_size; + u8 raw_data[EC_MAILBOX_DATA_SIZE_EXTENDED]; + u8 formatted_data[FORMATTED_BUFFER_SIZE]; +}; +static struct wilco_ec_debugfs *debug_info; + +/** + * parse_hex_sentence() - Convert a ascii hex representation into byte array. + * @in: Input buffer of ascii. + * @isize: Length of input buffer. + * @out: Output buffer. + * @osize: Length of output buffer, e.g. max number of bytes to parse. + * + * An valid input is a series of ascii hexadecimal numbers, separated by spaces. + * An example valid input is + * " 00 f2 0 000076 6 0 ff" + * + * If an individual "word" within the hex sentence is longer than MAX_WORD_SIZE, + * then the sentence is illegal, and parsing will fail. + * + * Return: Number of bytes parsed, or negative error code on failure. + */ +static int parse_hex_sentence(const char *in, int isize, u8 *out, int osize) +{ + int n_parsed = 0; + int word_start = 0; + int word_end; + int word_len; + /* Temp buffer for holding a "word" of chars that represents one byte */ + #define MAX_WORD_SIZE 16 + char tmp[MAX_WORD_SIZE + 1]; + u8 byte; + + while (word_start < isize && n_parsed < osize) { + /* Find the start of the next word */ + while (word_start < isize && isspace(in[word_start])) + word_start++; + /* reached the end of the input before next word? */ + if (word_start >= isize) + break; + + /* Find the end of this word */ + word_end = word_start; + while (word_end < isize && !isspace(in[word_end])) + word_end++; + + /* Copy to a tmp NULL terminated string */ + word_len = word_end - word_start; + if (word_len > MAX_WORD_SIZE) + return -EINVAL; + memcpy(tmp, in + word_start, word_len); + tmp[word_len] = '\0'; + + /* + * Convert from hex string, place in output. If fails to parse, + * just return -EINVAL because specific error code is only + * relevant for this one word, returning it would be confusing. + */ + if (kstrtou8(tmp, 16, &byte)) + return -EINVAL; + out[n_parsed++] = byte; + + word_start = word_end; + } + return n_parsed; +} + +/* The message type takes up two bytes*/ +#define TYPE_AND_DATA_SIZE ((EC_MAILBOX_DATA_SIZE) + 2) + +static ssize_t raw_write(struct file *file, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + char *buf = debug_info->formatted_data; + struct wilco_ec_message msg; + u8 request_data[TYPE_AND_DATA_SIZE]; + ssize_t kcount; + int ret; + + if (count > FORMATTED_BUFFER_SIZE) + return -EINVAL; + + kcount = simple_write_to_buffer(buf, FORMATTED_BUFFER_SIZE, ppos, + user_buf, count); + if (kcount < 0) + return kcount; + + ret = parse_hex_sentence(buf, kcount, request_data, TYPE_AND_DATA_SIZE); + if (ret < 0) + return ret; + /* Need at least two bytes for message type and one for command */ + if (ret < 3) + return -EINVAL; + + /* Clear response data buffer */ + memset(debug_info->raw_data, '\0', EC_MAILBOX_DATA_SIZE_EXTENDED); + + msg.type = request_data[0] << 8 | request_data[1]; + msg.flags = WILCO_EC_FLAG_RAW; + msg.command = request_data[2]; + msg.request_data = ret > 3 ? request_data + 3 : 0; + msg.request_size = ret - 3; + msg.response_data = debug_info->raw_data; + msg.response_size = EC_MAILBOX_DATA_SIZE; + + /* Telemetry commands use extended response data */ + if (msg.type == WILCO_EC_MSG_TELEMETRY_LONG) { + msg.flags |= WILCO_EC_FLAG_EXTENDED_DATA; + msg.response_size = EC_MAILBOX_DATA_SIZE_EXTENDED; + } + + ret = wilco_ec_mailbox(debug_info->ec, &msg); + if (ret < 0) + return ret; + debug_info->response_size = ret; + + return count; +} + +static ssize_t raw_read(struct file *file, char __user *user_buf, size_t count, + loff_t *ppos) +{ + int fmt_len = 0; + + if (debug_info->response_size) { + fmt_len = hex_dump_to_buffer(debug_info->raw_data, + debug_info->response_size, + 16, 1, debug_info->formatted_data, + FORMATTED_BUFFER_SIZE, true); + /* Only return response the first time it is read */ + debug_info->response_size = 0; + } + + return simple_read_from_buffer(user_buf, count, ppos, + debug_info->formatted_data, fmt_len); +} + +static const struct file_operations fops_raw = { + .owner = THIS_MODULE, + .read = raw_read, + .write = raw_write, + .llseek = no_llseek, +}; + +/** + * wilco_ec_debugfs_probe() - Create the debugfs node + * @pdev: The platform device, probably created in core.c + * + * Try to create a debugfs node. If it fails, then we don't want to change + * behavior at all, this is for debugging after all. Just fail silently. + * + * Return: 0 always. + */ +static int wilco_ec_debugfs_probe(struct platform_device *pdev) +{ + struct wilco_ec_device *ec = dev_get_drvdata(pdev->dev.parent); + + debug_info = devm_kzalloc(&pdev->dev, sizeof(*debug_info), GFP_KERNEL); + if (!debug_info) + return 0; + debug_info->ec = ec; + debug_info->dir = debugfs_create_dir("wilco_ec", NULL); + if (!debug_info->dir) + return 0; + debugfs_create_file("raw", 0644, debug_info->dir, NULL, &fops_raw); + + return 0; +} + +static int wilco_ec_debugfs_remove(struct platform_device *pdev) +{ + debugfs_remove_recursive(debug_info->dir); + + return 0; +} + +static struct platform_driver wilco_ec_debugfs_driver = { + .driver = { + .name = DRV_NAME, + }, + .probe = wilco_ec_debugfs_probe, + .remove = wilco_ec_debugfs_remove, +}; + +module_platform_driver(wilco_ec_debugfs_driver); + +MODULE_ALIAS("platform:" DRV_NAME); +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Wilco EC debugfs driver"); diff --git a/drivers/platform/chrome/wilco_ec/mailbox.c b/drivers/platform/chrome/wilco_ec/mailbox.c @@ -0,0 +1,237 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Mailbox interface for Wilco Embedded Controller + * + * Copyright 2018 Google LLC + * + * The Wilco EC is similar to a typical ChromeOS embedded controller. + * It uses the same MEC based low-level communication and a similar + * protocol, but with some important differences. The EC firmware does + * not support the same mailbox commands so it is not registered as a + * cros_ec device type. + * + * Most messages follow a standard format, but there are some exceptions + * and an interface is provided to do direct/raw transactions that do not + * make assumptions about byte placement. + */ + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/platform_device.h> + +#include "../cros_ec_lpc_mec.h" + +/* Version of mailbox interface */ +#define EC_MAILBOX_VERSION 0 + +/* Command to start mailbox transaction */ +#define EC_MAILBOX_START_COMMAND 0xda + +/* Version of EC protocol */ +#define EC_MAILBOX_PROTO_VERSION 3 + +/* Number of header bytes to be counted as data bytes */ +#define EC_MAILBOX_DATA_EXTRA 2 + +/* Maximum timeout */ +#define EC_MAILBOX_TIMEOUT HZ + +/* EC response flags */ +#define EC_CMDR_DATA BIT(0) /* Data ready for host to read */ +#define EC_CMDR_PENDING BIT(1) /* Write pending to EC */ +#define EC_CMDR_BUSY BIT(2) /* EC is busy processing a command */ +#define EC_CMDR_CMD BIT(3) /* Last host write was a command */ + +/** + * wilco_ec_response_timed_out() - Wait for EC response. + * @ec: EC device. + * + * Return: true if EC timed out, false if EC did not time out. + */ +static bool wilco_ec_response_timed_out(struct wilco_ec_device *ec) +{ + unsigned long timeout = jiffies + EC_MAILBOX_TIMEOUT; + + do { + if (!(inb(ec->io_command->start) & + (EC_CMDR_PENDING | EC_CMDR_BUSY))) + return false; + usleep_range(100, 200); + } while (time_before(jiffies, timeout)); + + return true; +} + +/** + * wilco_ec_checksum() - Compute 8-bit checksum over data range. + * @data: Data to checksum. + * @size: Number of bytes to checksum. + * + * Return: 8-bit checksum of provided data. + */ +static u8 wilco_ec_checksum(const void *data, size_t size) +{ + u8 *data_bytes = (u8 *)data; + u8 checksum = 0; + size_t i; + + for (i = 0; i < size; i++) + checksum += data_bytes[i]; + + return checksum; +} + +/** + * wilco_ec_prepare() - Prepare the request structure for the EC. + * @msg: EC message with request information. + * @rq: EC request structure to fill. + */ +static void wilco_ec_prepare(struct wilco_ec_message *msg, + struct wilco_ec_request *rq) +{ + memset(rq, 0, sizeof(*rq)); + + /* Handle messages without trimming bytes from the request */ + if (msg->request_size && msg->flags & WILCO_EC_FLAG_RAW_REQUEST) { + rq->reserved_raw = *(u8 *)msg->request_data; + msg->request_size--; + memmove(msg->request_data, msg->request_data + 1, + msg->request_size); + } + + /* Fill in request packet */ + rq->struct_version = EC_MAILBOX_PROTO_VERSION; + rq->mailbox_id = msg->type; + rq->mailbox_version = EC_MAILBOX_VERSION; + rq->data_size = msg->request_size + EC_MAILBOX_DATA_EXTRA; + rq->command = msg->command; + + /* Checksum header and data */ + rq->checksum = wilco_ec_checksum(rq, sizeof(*rq)); + rq->checksum += wilco_ec_checksum(msg->request_data, msg->request_size); + rq->checksum = -rq->checksum; +} + +/** + * wilco_ec_transfer() - Perform actual data transfer. + * @ec: EC device. + * @msg: EC message data for request and response. + * @rq: Filled in request structure + * + * Context: ec->mailbox_lock should be held while using this function. + * Return: number of bytes received or negative error code on failure. + */ +static int wilco_ec_transfer(struct wilco_ec_device *ec, + struct wilco_ec_message *msg, + struct wilco_ec_request *rq) +{ + struct wilco_ec_response *rs; + u8 checksum; + u8 flag; + size_t size; + + /* Write request header, then data */ + cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, 0, sizeof(*rq), (u8 *)rq); + cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, sizeof(*rq), msg->request_size, + msg->request_data); + + /* Start the command */ + outb(EC_MAILBOX_START_COMMAND, ec->io_command->start); + + /* For some commands (eg shutdown) the EC will not respond, that's OK */ + if (msg->flags & WILCO_EC_FLAG_NO_RESPONSE) { + dev_dbg(ec->dev, "EC does not respond to this command\n"); + return 0; + } + + /* Wait for it to complete */ + if (wilco_ec_response_timed_out(ec)) { + dev_dbg(ec->dev, "response timed out\n"); + return -ETIMEDOUT; + } + + /* Check result */ + flag = inb(ec->io_data->start); + if (flag) { + dev_dbg(ec->dev, "bad response: 0x%02x\n", flag); + return -EIO; + } + + if (msg->flags & WILCO_EC_FLAG_EXTENDED_DATA) + size = EC_MAILBOX_DATA_SIZE_EXTENDED; + else + size = EC_MAILBOX_DATA_SIZE; + + /* Read back response */ + rs = ec->data_buffer; + checksum = cros_ec_lpc_io_bytes_mec(MEC_IO_READ, 0, + sizeof(*rs) + size, (u8 *)rs); + if (checksum) { + dev_dbg(ec->dev, "bad packet checksum 0x%02x\n", rs->checksum); + return -EBADMSG; + } + + /* Check that the EC reported success */ + msg->result = rs->result; + if (msg->result) { + dev_dbg(ec->dev, "bad response: 0x%02x\n", msg->result); + return -EBADMSG; + } + + /* Check the returned data size, skipping the header */ + if (rs->data_size != size) { + dev_dbg(ec->dev, "unexpected packet size (%u != %zu)", + rs->data_size, size); + return -EMSGSIZE; + } + + /* Skip 1 response data byte unless specified */ + size = (msg->flags & WILCO_EC_FLAG_RAW_RESPONSE) ? 0 : 1; + if ((ssize_t) rs->data_size - size < msg->response_size) { + dev_dbg(ec->dev, "response data too short (%zd < %zu)", + (ssize_t) rs->data_size - size, msg->response_size); + return -EMSGSIZE; + } + + /* Ignore response data bytes as requested */ + memcpy(msg->response_data, rs->data + size, msg->response_size); + + /* Return actual amount of data received */ + return msg->response_size; +} + +/** + * wilco_ec_mailbox() - Send EC request and receive EC response. + * @ec: EC device. + * @msg: EC message data for request and response. + * + * On entry msg->type, msg->flags, msg->command, msg->request_size, + * msg->response_size, and msg->request_data should all be filled in. + * + * On exit msg->result and msg->response_data will be filled. + * + * Return: number of bytes received or negative error code on failure. + */ +int wilco_ec_mailbox(struct wilco_ec_device *ec, struct wilco_ec_message *msg) +{ + struct wilco_ec_request *rq; + int ret; + + dev_dbg(ec->dev, "cmd=%02x type=%04x flags=%02x rslen=%zu rqlen=%zu\n", + msg->command, msg->type, msg->flags, msg->response_size, + msg->request_size); + + /* Prepare request packet */ + rq = ec->data_buffer; + wilco_ec_prepare(msg, rq); + + mutex_lock(&ec->mailbox_lock); + ret = wilco_ec_transfer(ec, msg, rq); + mutex_unlock(&ec->mailbox_lock); + + return ret; + +} +EXPORT_SYMBOL_GPL(wilco_ec_mailbox); diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig @@ -1864,4 +1864,15 @@ config RTC_DRV_GOLDFISH Goldfish is a code name for the virtual platform developed by Google for Android emulation. +config RTC_DRV_WILCO_EC + tristate "Wilco EC RTC" + depends on WILCO_EC + default m + help + If you say yes here, you get read/write support for the Real Time + Clock on the Wilco Embedded Controller (Wilco is a kind of Chromebook) + + This can also be built as a module. If so, the module will + be named "rtc_wilco_ec". + endif # RTC_CLASS diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile @@ -177,6 +177,7 @@ obj-$(CONFIG_RTC_DRV_V3020) += rtc-v3020.o obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41xx.o obj-$(CONFIG_RTC_DRV_VRTC) += rtc-mrst.o obj-$(CONFIG_RTC_DRV_VT8500) += rtc-vt8500.o +obj-$(CONFIG_RTC_DRV_WILCO_EC) += rtc-wilco-ec.o obj-$(CONFIG_RTC_DRV_WM831X) += rtc-wm831x.o obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c @@ -0,0 +1,177 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RTC interface for Wilco Embedded Controller with R/W abilities + * + * Copyright 2018 Google LLC + * + * The corresponding platform device is typically registered in + * drivers/platform/chrome/wilco_ec/core.c + */ + +#include <linux/bcd.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/rtc.h> +#include <linux/timekeeping.h> + +#define EC_COMMAND_CMOS 0x7c +#define EC_CMOS_TOD_WRITE 0x02 +#define EC_CMOS_TOD_READ 0x08 + +/** + * struct ec_rtc_read - Format of RTC returned by EC. + * @second: Second value (0..59) + * @minute: Minute value (0..59) + * @hour: Hour value (0..23) + * @day: Day value (1..31) + * @month: Month value (1..12) + * @year: Year value (full year % 100) + * @century: Century value (full year / 100) + * + * All values are presented in binary (not BCD). + */ +struct ec_rtc_read { + u8 second; + u8 minute; + u8 hour; + u8 day; + u8 month; + u8 year; + u8 century; +} __packed; + +/** + * struct ec_rtc_write - Format of RTC sent to the EC. + * @param: EC_CMOS_TOD_WRITE + * @century: Century value (full year / 100) + * @year: Year value (full year % 100) + * @month: Month value (1..12) + * @day: Day value (1..31) + * @hour: Hour value (0..23) + * @minute: Minute value (0..59) + * @second: Second value (0..59) + * @weekday: Day of the week (0=Saturday) + * + * All values are presented in BCD. + */ +struct ec_rtc_write { + u8 param; + u8 century; + u8 year; + u8 month; + u8 day; + u8 hour; + u8 minute; + u8 second; + u8 weekday; +} __packed; + +static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm) +{ + struct wilco_ec_device *ec = dev_get_drvdata(dev->parent); + u8 param = EC_CMOS_TOD_READ; + struct ec_rtc_read rtc; + struct wilco_ec_message msg = { + .type = WILCO_EC_MSG_LEGACY, + .flags = WILCO_EC_FLAG_RAW_RESPONSE, + .command = EC_COMMAND_CMOS, + .request_data = &param, + .request_size = sizeof(param), + .response_data = &rtc, + .response_size = sizeof(rtc), + }; + int ret; + + ret = wilco_ec_mailbox(ec, &msg); + if (ret < 0) + return ret; + + tm->tm_sec = rtc.second; + tm->tm_min = rtc.minute; + tm->tm_hour = rtc.hour; + tm->tm_mday = rtc.day; + tm->tm_mon = rtc.month - 1; + tm->tm_year = rtc.year + (rtc.century * 100) - 1900; + tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); + + /* Don't compute day of week, we don't need it. */ + tm->tm_wday = -1; + + return 0; +} + +static int wilco_ec_rtc_write(struct device *dev, struct rtc_time *tm) +{ + struct wilco_ec_device *ec = dev_get_drvdata(dev->parent); + struct ec_rtc_write rtc; + struct wilco_ec_message msg = { + .type = WILCO_EC_MSG_LEGACY, + .flags = WILCO_EC_FLAG_RAW_RESPONSE, + .command = EC_COMMAND_CMOS, + .request_data = &rtc, + .request_size = sizeof(rtc), + }; + int year = tm->tm_year + 1900; + /* + * Convert from 0=Sunday to 0=Saturday for the EC + * We DO need to set weekday because the EC controls battery charging + * schedules that depend on the day of the week. + */ + int wday = tm->tm_wday == 6 ? 0 : tm->tm_wday + 1; + int ret; + + rtc.param = EC_CMOS_TOD_WRITE; + rtc.century = bin2bcd(year / 100); + rtc.year = bin2bcd(year % 100); + rtc.month = bin2bcd(tm->tm_mon + 1); + rtc.day = bin2bcd(tm->tm_mday); + rtc.hour = bin2bcd(tm->tm_hour); + rtc.minute = bin2bcd(tm->tm_min); + rtc.second = bin2bcd(tm->tm_sec); + rtc.weekday = bin2bcd(wday); + + ret = wilco_ec_mailbox(ec, &msg); + if (ret < 0) + return ret; + + return 0; +} + +static const struct rtc_class_ops wilco_ec_rtc_ops = { + .read_time = wilco_ec_rtc_read, + .set_time = wilco_ec_rtc_write, +}; + +static int wilco_ec_rtc_probe(struct platform_device *pdev) +{ + struct rtc_device *rtc; + + rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + rtc->ops = &wilco_ec_rtc_ops; + /* EC only supports this century */ + rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->range_max = RTC_TIMESTAMP_END_2099; + rtc->owner = THIS_MODULE; + + return rtc_register_device(rtc); +} + +static struct platform_driver wilco_ec_rtc_driver = { + .driver = { + .name = "rtc-wilco-ec", + }, + .probe = wilco_ec_rtc_probe, +}; + +module_platform_driver(wilco_ec_rtc_driver); + +MODULE_ALIAS("platform:rtc-wilco-ec"); +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Wilco EC RTC driver"); diff --git a/include/linux/platform_data/wilco-ec.h b/include/linux/platform_data/wilco-ec.h @@ -0,0 +1,144 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * ChromeOS Wilco Embedded Controller + * + * Copyright 2018 Google LLC + */ + +#ifndef WILCO_EC_H +#define WILCO_EC_H + +#include <linux/device.h> +#include <linux/kernel.h> + +/* Message flags for using the mailbox() interface */ +#define WILCO_EC_FLAG_NO_RESPONSE BIT(0) /* EC does not respond */ +#define WILCO_EC_FLAG_EXTENDED_DATA BIT(1) /* EC returns 256 data bytes */ +#define WILCO_EC_FLAG_RAW_REQUEST BIT(2) /* Do not trim request data */ +#define WILCO_EC_FLAG_RAW_RESPONSE BIT(3) /* Do not trim response data */ +#define WILCO_EC_FLAG_RAW (WILCO_EC_FLAG_RAW_REQUEST | \ + WILCO_EC_FLAG_RAW_RESPONSE) + +/* Normal commands have a maximum 32 bytes of data */ +#define EC_MAILBOX_DATA_SIZE 32 +/* Extended commands have 256 bytes of response data */ +#define EC_MAILBOX_DATA_SIZE_EXTENDED 256 + +/** + * struct wilco_ec_device - Wilco Embedded Controller handle. + * @dev: Device handle. + * @mailbox_lock: Mutex to ensure one mailbox command at a time. + * @io_command: I/O port for mailbox command. Provided by ACPI. + * @io_data: I/O port for mailbox data. Provided by ACPI. + * @io_packet: I/O port for mailbox packet data. Provided by ACPI. + * @data_buffer: Buffer used for EC communication. The same buffer + * is used to hold the request and the response. + * @data_size: Size of the data buffer used for EC communication. + * @debugfs_pdev: The child platform_device used by the debugfs sub-driver. + * @rtc_pdev: The child platform_device used by the RTC sub-driver. + */ +struct wilco_ec_device { + struct device *dev; + struct mutex mailbox_lock; + struct resource *io_command; + struct resource *io_data; + struct resource *io_packet; + void *data_buffer; + size_t data_size; + struct platform_device *debugfs_pdev; + struct platform_device *rtc_pdev; +}; + +/** + * struct wilco_ec_request - Mailbox request message format. + * @struct_version: Should be %EC_MAILBOX_PROTO_VERSION + * @checksum: Sum of all bytes must be 0. + * @mailbox_id: Mailbox identifier, specifies the command set. + * @mailbox_version: Mailbox interface version %EC_MAILBOX_VERSION + * @reserved: Set to zero. + * @data_size: Length of request, data + last 2 bytes of the header. + * @command: Mailbox command code, unique for each mailbox_id set. + * @reserved_raw: Set to zero for most commands, but is used by + * some command types and for raw commands. + */ +struct wilco_ec_request { + u8 struct_version; + u8 checksum; + u16 mailbox_id; + u8 mailbox_version; + u8 reserved; + u16 data_size; + u8 command; + u8 reserved_raw; +} __packed; + +/** + * struct wilco_ec_response - Mailbox response message format. + * @struct_version: Should be %EC_MAILBOX_PROTO_VERSION + * @checksum: Sum of all bytes must be 0. + * @result: Result code from the EC. Non-zero indicates an error. + * @data_size: Length of the response data buffer. + * @reserved: Set to zero. + * @mbox0: EC returned data at offset 0 is unused (always 0) so this byte + * is treated as part of the header instead of the data. + * @data: Response data buffer. Max size is %EC_MAILBOX_DATA_SIZE_EXTENDED. + */ +struct wilco_ec_response { + u8 struct_version; + u8 checksum; + u16 result; + u16 data_size; + u8 reserved[2]; + u8 mbox0; + u8 data[0]; +} __packed; + +/** + * enum wilco_ec_msg_type - Message type to select a set of command codes. + * @WILCO_EC_MSG_LEGACY: Legacy EC messages for standard EC behavior. + * @WILCO_EC_MSG_PROPERTY: Get/Set/Sync EC controlled NVRAM property. + * @WILCO_EC_MSG_TELEMETRY_SHORT: 32 bytes of telemetry data provided by the EC. + * @WILCO_EC_MSG_TELEMETRY_LONG: 256 bytes of telemetry data provided by the EC. + */ +enum wilco_ec_msg_type { + WILCO_EC_MSG_LEGACY = 0x00f0, + WILCO_EC_MSG_PROPERTY = 0x00f2, + WILCO_EC_MSG_TELEMETRY_SHORT = 0x00f5, + WILCO_EC_MSG_TELEMETRY_LONG = 0x00f6, +}; + +/** + * struct wilco_ec_message - Request and response message. + * @type: Mailbox message type. + * @flags: Message flags, e.g. %WILCO_EC_FLAG_NO_RESPONSE. + * @command: Mailbox command code. + * @result: Result code from the EC. Non-zero indicates an error. + * @request_size: Number of bytes to send to the EC. + * @request_data: Buffer containing the request data. + * @response_size: Number of bytes expected from the EC. + * This is 32 by default and 256 if the flag + * is set for %WILCO_EC_FLAG_EXTENDED_DATA + * @response_data: Buffer containing the response data, should be + * response_size bytes and allocated by caller. + */ +struct wilco_ec_message { + enum wilco_ec_msg_type type; + u8 flags; + u8 command; + u8 result; + size_t request_size; + void *request_data; + size_t response_size; + void *response_data; +}; + +/** + * wilco_ec_mailbox() - Send request to the EC and receive the response. + * @ec: Wilco EC device. + * @msg: Wilco EC message. + * + * Return: Number of bytes received or negative error code on failure. + */ +int wilco_ec_mailbox(struct wilco_ec_device *ec, struct wilco_ec_message *msg); + +#endif /* WILCO_EC_H */