diff options
Diffstat (limited to 'drivers/mfd')
| -rw-r--r-- | drivers/mfd/Kconfig | 18 | ||||
| -rw-r--r-- | drivers/mfd/Makefile | 3 | ||||
| -rw-r--r-- | drivers/mfd/cros_ec.c | 4 | ||||
| -rw-r--r-- | drivers/mfd/cros_ec_dev.c | 552 | ||||
| -rw-r--r-- | drivers/mfd/cros_ec_dev.h | 52 | ||||
| -rw-r--r-- | drivers/mfd/rave-sp.c | 710 |
6 files changed, 1337 insertions, 2 deletions
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 1246ba1832d7..fb884fab0b8d 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -222,6 +222,16 @@ config MFD_CROS_EC_SPI response time cannot be guaranteed, we support ignoring 'pre-amble' bytes before the response actually starts. +config MFD_CROS_EC_CHARDEV + tristate "Chrome OS Embedded Controller userspace device interface" + depends on MFD_CROS_EC + select CROS_EC_CTL + ---help--- + This driver adds support to talk with the ChromeOS EC from userspace. + + If you have a supported Chromebook, choose Y or M here. + The module will be called cros_ec_dev. + config MFD_ASIC3 bool "Compaq ASIC3" depends on GPIOLIB && ARM @@ -1838,5 +1848,13 @@ config MFD_VEXPRESS_SYSREG System Registers are the platform configuration block on the ARM Ltd. Versatile Express board. +config RAVE_SP_CORE + tristate "RAVE SP MCU core driver" + depends on SERIAL_DEV_BUS + select CRC_CCITT + help + Select this to get support for the Supervisory Processor + device found on several devices in RAVE line of hardware. + endmenu endif diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index 293e223c373d..d9d2cf0d32ef 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -17,6 +17,7 @@ cros_ec_core-$(CONFIG_ACPI) += cros_ec_acpi_gpe.o obj-$(CONFIG_MFD_CROS_EC) += cros_ec_core.o obj-$(CONFIG_MFD_CROS_EC_I2C) += cros_ec_i2c.o obj-$(CONFIG_MFD_CROS_EC_SPI) += cros_ec_spi.o +obj-$(CONFIG_MFD_CROS_EC_CHARDEV) += cros_ec_dev.o obj-$(CONFIG_MFD_EXYNOS_LPASS) += exynos-lpass.o obj-$(CONFIG_HTC_PASIC3) += htc-pasic3.o @@ -226,3 +227,5 @@ obj-$(CONFIG_MFD_STM32_LPTIMER) += stm32-lptimer.o obj-$(CONFIG_MFD_STM32_TIMERS) += stm32-timers.o obj-$(CONFIG_MFD_MXS_LRADC) += mxs-lradc.o obj-$(CONFIG_MFD_SC27XX_PMIC) += sprd-sc27xx-spi.o +obj-$(CONFIG_RAVE_SP_CORE) += rave-sp.o + diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c index b0ca5a4c841e..d61024141e2b 100644 --- a/drivers/mfd/cros_ec.c +++ b/drivers/mfd/cros_ec.c @@ -40,13 +40,13 @@ static struct cros_ec_platform pd_p = { }; static const struct mfd_cell ec_cell = { - .name = "cros-ec-ctl", + .name = "cros-ec-dev", .platform_data = &ec_p, .pdata_size = sizeof(ec_p), }; static const struct mfd_cell ec_pd_cell = { - .name = "cros-ec-ctl", + .name = "cros-ec-dev", .platform_data = &pd_p, .pdata_size = sizeof(pd_p), }; diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c new file mode 100644 index 000000000000..e4fafdd96e5e --- /dev/null +++ b/drivers/mfd/cros_ec_dev.c @@ -0,0 +1,552 @@ +/* + * cros_ec_dev - expose the Chrome OS Embedded Controller to user-space + * + * 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/>. + */ + +#include <linux/fs.h> +#include <linux/mfd/core.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/uaccess.h> + +#include "cros_ec_dev.h" + +#define DRV_NAME "cros-ec-dev" + +/* Device variables */ +#define CROS_MAX_DEV 128 +static int ec_major; + +static const struct attribute_group *cros_ec_groups[] = { + &cros_ec_attr_group, + &cros_ec_lightbar_attr_group, + &cros_ec_vbc_attr_group, + NULL, +}; + +static struct class cros_class = { + .owner = THIS_MODULE, + .name = "chromeos", + .dev_groups = cros_ec_groups, +}; + +/* Basic communication */ +static int ec_get_version(struct cros_ec_dev *ec, char *str, int maxlen) +{ + struct ec_response_get_version *resp; + static const char * const current_image_name[] = { + "unknown", "read-only", "read-write", "invalid", + }; + struct cros_ec_command *msg; + int ret; + + msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->version = 0; + msg->command = EC_CMD_GET_VERSION + ec->cmd_offset; + msg->insize = sizeof(*resp); + msg->outsize = 0; + + ret = cros_ec_cmd_xfer(ec->ec_dev, msg); + if (ret < 0) + goto exit; + + if (msg->result != EC_RES_SUCCESS) { + snprintf(str, maxlen, + "%s\nUnknown EC version: EC returned %d\n", + CROS_EC_DEV_VERSION, msg->result); + ret = -EINVAL; + goto exit; + } + + resp = (struct ec_response_get_version *)msg->data; + if (resp->current_image >= ARRAY_SIZE(current_image_name)) + resp->current_image = 3; /* invalid */ + + snprintf(str, maxlen, "%s\n%s\n%s\n%s\n", CROS_EC_DEV_VERSION, + resp->version_string_ro, resp->version_string_rw, + current_image_name[resp->current_image]); + + ret = 0; +exit: + kfree(msg); + return ret; +} + +static int cros_ec_check_features(struct cros_ec_dev *ec, int feature) +{ + struct cros_ec_command *msg; + int ret; + + if (ec->features[0] == -1U && ec->features[1] == -1U) { + /* features bitmap not read yet */ + + msg = kmalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->version = 0; + msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset; + msg->insize = sizeof(ec->features); + msg->outsize = 0; + + ret = cros_ec_cmd_xfer(ec->ec_dev, msg); + if (ret < 0 || msg->result != EC_RES_SUCCESS) { + dev_warn(ec->dev, "cannot get EC features: %d/%d\n", + ret, msg->result); + memset(ec->features, 0, sizeof(ec->features)); + } + + memcpy(ec->features, msg->data, sizeof(ec->features)); + + dev_dbg(ec->dev, "EC features %08x %08x\n", + ec->features[0], ec->features[1]); + + kfree(msg); + } + + return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature); +} + +/* Device file ops */ +static int ec_device_open(struct inode *inode, struct file *filp) +{ + struct cros_ec_dev *ec = container_of(inode->i_cdev, + struct cros_ec_dev, cdev); + filp->private_data = ec; + nonseekable_open(inode, filp); + return 0; +} + +static int ec_device_release(struct inode *inode, struct file *filp) +{ + return 0; +} + +static ssize_t ec_device_read(struct file *filp, char __user *buffer, + size_t length, loff_t *offset) +{ + struct cros_ec_dev *ec = filp->private_data; + char msg[sizeof(struct ec_response_get_version) + + sizeof(CROS_EC_DEV_VERSION)]; + size_t count; + int ret; + + if (*offset != 0) + return 0; + + ret = ec_get_version(ec, msg, sizeof(msg)); + if (ret) + return ret; + + count = min(length, strlen(msg)); + + if (copy_to_user(buffer, msg, count)) + return -EFAULT; + + *offset = count; + return count; +} + +/* Ioctls */ +static long ec_device_ioctl_xcmd(struct cros_ec_dev *ec, void __user *arg) +{ + long ret; + struct cros_ec_command u_cmd; + struct cros_ec_command *s_cmd; + + if (copy_from_user(&u_cmd, arg, sizeof(u_cmd))) + return -EFAULT; + + if ((u_cmd.outsize > EC_MAX_MSG_BYTES) || + (u_cmd.insize > EC_MAX_MSG_BYTES)) + return -EINVAL; + + s_cmd = kmalloc(sizeof(*s_cmd) + max(u_cmd.outsize, u_cmd.insize), + GFP_KERNEL); + if (!s_cmd) + return -ENOMEM; + + if (copy_from_user(s_cmd, arg, sizeof(*s_cmd) + u_cmd.outsize)) { + ret = -EFAULT; + goto exit; + } + + if (u_cmd.outsize != s_cmd->outsize || + u_cmd.insize != s_cmd->insize) { + ret = -EINVAL; + goto exit; + } + + s_cmd->command += ec->cmd_offset; + ret = cros_ec_cmd_xfer(ec->ec_dev, s_cmd); + /* Only copy data to userland if data was received. */ + if (ret < 0) + goto exit; + + if (copy_to_user(arg, s_cmd, sizeof(*s_cmd) + s_cmd->insize)) + ret = -EFAULT; +exit: + kfree(s_cmd); + return ret; +} + +static long ec_device_ioctl_readmem(struct cros_ec_dev *ec, void __user *arg) +{ + struct cros_ec_device *ec_dev = ec->ec_dev; + struct cros_ec_readmem s_mem = { }; + long num; + + /* Not every platform supports direct reads */ + if (!ec_dev->cmd_readmem) + return -ENOTTY; + + if (copy_from_user(&s_mem, arg, sizeof(s_mem))) + return -EFAULT; + + num = ec_dev->cmd_readmem(ec_dev, s_mem.offset, s_mem.bytes, + s_mem.buffer); + if (num <= 0) + return num; + + if (copy_to_user((void __user *)arg, &s_mem, sizeof(s_mem))) + return -EFAULT; + + return 0; +} + +static long ec_device_ioctl(struct file *filp, unsigned int cmd, + unsigned long arg) +{ + struct cros_ec_dev *ec = filp->private_data; + + if (_IOC_TYPE(cmd) != CROS_EC_DEV_IOC) + return -ENOTTY; + + switch (cmd) { + case CROS_EC_DEV_IOCXCMD: + return ec_device_ioctl_xcmd(ec, (void __user *)arg); + case CROS_EC_DEV_IOCRDMEM: + return ec_device_ioctl_readmem(ec, (void __user *)arg); + } + + return -ENOTTY; +} + +/* Module initialization */ +static const struct file_operations fops = { + .open = ec_device_open, + .release = ec_device_release, + .read = ec_device_read, + .unlocked_ioctl = ec_device_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = ec_device_ioctl, +#endif +}; + +static void __remove(struct device *dev) +{ + struct cros_ec_dev *ec = container_of(dev, struct cros_ec_dev, + class_dev); + kfree(ec); +} + +static void cros_ec_sensors_register(struct cros_ec_dev *ec) +{ + /* + * Issue a command to get the number of sensor reported. + * Build an array of sensors driver and register them all. + */ + int ret, i, id, sensor_num; + struct mfd_cell *sensor_cells; + struct cros_ec_sensor_platform *sensor_platforms; + int sensor_type[MOTIONSENSE_TYPE_MAX]; + struct ec_params_motion_sense *params; + struct ec_response_motion_sense *resp; + struct cros_ec_command *msg; + + msg = kzalloc(sizeof(struct cros_ec_command) + + max(sizeof(*params), sizeof(*resp)), GFP_KERNEL); + if (msg == NULL) + return; + + msg->version = 2; + msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset; + msg->outsize = sizeof(*params); + msg->insize = sizeof(*resp); + + params = (struct ec_params_motion_sense *)msg->data; + params->cmd = MOTIONSENSE_CMD_DUMP; + + ret = cros_ec_cmd_xfer(ec->ec_dev, msg); + if (ret < 0 || msg->result != EC_RES_SUCCESS) { + dev_warn(ec->dev, "cannot get EC sensor information: %d/%d\n", + ret, msg->result); + goto error; + } + + resp = (struct ec_response_motion_sense *)msg->data; + sensor_num = resp->dump.sensor_count; + /* Allocate 2 extra sensors in case lid angle or FIFO are needed */ + sensor_cells = kzalloc(sizeof(struct mfd_cell) * (sensor_num + 2), + GFP_KERNEL); + if (sensor_cells == NULL) + goto error; + + sensor_platforms = kzalloc(sizeof(struct cros_ec_sensor_platform) * + (sensor_num + 1), GFP_KERNEL); + if (sensor_platforms == NULL) + goto error_platforms; + + memset(sensor_type, 0, sizeof(sensor_type)); + id = 0; + for (i = 0; i < sensor_num; i++) { + params->cmd = MOTIONSENSE_CMD_INFO; + params->info.sensor_num = i; + ret = cros_ec_cmd_xfer(ec->ec_dev, msg); + if (ret < 0 || msg->result != EC_RES_SUCCESS) { + dev_warn(ec->dev, "no info for EC sensor %d : %d/%d\n", + i, ret, msg->result); + continue; + } + switch (resp->info.type) { + case MOTIONSENSE_TYPE_ACCEL: + sensor_cells[id].name = "cros-ec-accel"; + break; + case MOTIONSENSE_TYPE_BARO: + sensor_cells[id].name = "cros-ec-baro"; + break; + case MOTIONSENSE_TYPE_GYRO: + sensor_cells[id].name = "cros-ec-gyro"; + break; + case MOTIONSENSE_TYPE_MAG: + sensor_cells[id].name = "cros-ec-mag"; + break; + case MOTIONSENSE_TYPE_PROX: + sensor_cells[id].name = "cros-ec-prox"; + break; + case MOTIONSENSE_TYPE_LIGHT: + sensor_cells[id].name = "cros-ec-light"; + break; + case MOTIONSENSE_TYPE_ACTIVITY: + sensor_cells[id].name = "cros-ec-activity"; + break; + default: + dev_warn(ec->dev, "unknown type %d\n", resp->info.type); + continue; + } + sensor_platforms[id].sensor_num = i; + sensor_cells[id].id = sensor_type[resp->info.type]; + sensor_cells[id].platform_data = &sensor_platforms[id]; + sensor_cells[id].pdata_size = + sizeof(struct cros_ec_sensor_platform); + + sensor_type[resp->info.type]++; + id++; + } + if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2) { + sensor_platforms[id].sensor_num = sensor_num; + + sensor_cells[id].name = "cros-ec-angle"; + sensor_cells[id].id = 0; + sensor_cells[id].platform_data = &sensor_platforms[id]; + sensor_cells[id].pdata_size = + sizeof(struct cros_ec_sensor_platform); + id++; + } + if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) { + sensor_cells[id].name = "cros-ec-ring"; + id++; + } + + ret = mfd_add_devices(ec->dev, 0, sensor_cells, id, + NULL, 0, NULL); + if (ret) + dev_err(ec->dev, "failed to add EC sensors\n"); + + kfree(sensor_platforms); +error_platforms: + kfree(sensor_cells); +error: + kfree(msg); +} + +static int ec_device_probe(struct platform_device *pdev) +{ + int retval = -ENOMEM; + struct device *dev = &pdev->dev; + struct cros_ec_platform *ec_platform = dev_get_platdata(dev); + struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL); + + if (!ec) + return retval; + + dev_set_drvdata(dev, ec); + ec->ec_dev = dev_get_drvdata(dev->parent); + ec->dev = dev; + ec->cmd_offset = ec_platform->cmd_offset; + ec->features[0] = -1U; /* Not cached yet */ + ec->features[1] = -1U; /* Not cached yet */ + device_initialize(&ec->class_dev); + cdev_init(&ec->cdev, &fops); + + /* + * Add the class device + * Link to the character device for creating the /dev entry + * in devtmpfs. + */ + ec->class_dev.devt = MKDEV(ec_major, pdev->id); + ec->class_dev.class = &cros_class; + ec->class_dev.parent = dev; + ec->class_dev.release = __remove; + + retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name); + if (retval) { + dev_err(dev, "dev_set_name failed => %d\n", retval); + goto failed; + } + + retval = cdev_device_add(&ec->cdev, &ec->class_dev); + if (retval) { + dev_err(dev, "cdev_device_add failed => %d\n", retval); + goto failed; + } + + if (cros_ec_debugfs_init(ec)) + dev_warn(dev, "failed to create debugfs directory\n"); + + /* check whether this EC is a sensor hub. */ + if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) + cros_ec_sensors_register(ec); + + /* Take control of the lightbar from the EC. */ + lb_manual_suspend_ctrl(ec, 1); + + return 0; + +failed: + put_device(&ec->class_dev); + return retval; +} + +static int ec_device_remove(struct platform_device *pdev) +{ + struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev); + + /* Let the EC take over the lightbar again. */ + lb_manual_suspend_ctrl(ec, 0); + + cros_ec_debugfs_remove(ec); + + cdev_del(&ec->cdev); + device_unregister(&ec->class_dev); + return 0; +} + +static const struct platform_device_id cros_ec_id[] = { + { DRV_NAME, 0 }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(platform, cros_ec_id); + +static __maybe_unused int ec_device_suspend(struct device *dev) +{ + struct cros_ec_dev *ec = dev_get_drvdata(dev); + + lb_suspend(ec); + + return 0; +} + +static __maybe_unused int ec_device_resume(struct device *dev) +{ + struct cros_ec_dev *ec = dev_get_drvdata(dev); + + lb_resume(ec); + + return 0; +} + +static const struct dev_pm_ops cros_ec_dev_pm_ops = { +#ifdef CONFIG_PM_SLEEP + .suspend = ec_device_suspend, + .resume = ec_device_resume, +#endif +}; + +static struct platform_driver cros_ec_dev_driver = { + .driver = { + .name = DRV_NAME, + .pm = &cros_ec_dev_pm_ops, + }, + .probe = ec_device_probe, + .remove = ec_device_remove, +}; + +static int __init cros_ec_dev_init(void) +{ + int ret; + dev_t dev = 0; + + ret = class_register(&cros_class); + if (ret) { + pr_err(CROS_EC_DEV_NAME ": failed to register device class\n"); + return ret; + } + + /* Get a range of minor numbers (starting with 0) to work with */ + ret = alloc_chrdev_region(&dev, 0, CROS_MAX_DEV, CROS_EC_DEV_NAME); + if (ret < 0) { + pr_err(CROS_EC_DEV_NAME ": alloc_chrdev_region() failed\n"); + goto failed_chrdevreg; + } + ec_major = MAJOR(dev); + + /* Register the driver */ + ret = platform_driver_register(&cros_ec_dev_driver); + if (ret < 0) { + pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret); + goto failed_devreg; + } + return 0; + +failed_devreg: + unregister_chrdev_region(MKDEV(ec_major, 0), CROS_MAX_DEV); +failed_chrdevreg: + class_unregister(&cros_class); + return ret; +} + +static void __exit cros_ec_dev_exit(void) +{ + platform_driver_unregister(&cros_ec_dev_driver); + unregister_chrdev(ec_major, CROS_EC_DEV_NAME); + class_unregister(&cros_class); +} + +module_init(cros_ec_dev_init); +module_exit(cros_ec_dev_exit); + +MODULE_ALIAS("platform:" DRV_NAME); +MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>"); +MODULE_DESCRIPTION("Userspace interface to the Chrome OS Embedded Controller"); +MODULE_VERSION("1.0"); +MODULE_LICENSE("GPL"); diff --git a/drivers/mfd/cros_ec_dev.h b/drivers/mfd/cros_ec_dev.h new file mode 100644 index 000000000000..45e9453608c5 --- /dev/null +++ b/drivers/mfd/cros_ec_dev.h @@ -0,0 +1,52 @@ +/* + * cros_ec_dev - expose the Chrome OS Embedded Controller 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/>. + */ + +#ifndef _CROS_EC_DEV_H_ +#define _CROS_EC_DEV_H_ + +#include <linux/ioctl.h> +#include <linux/types.h> +#include <linux/mfd/cros_ec.h> + +#define CROS_EC_DEV_VERSION "1.0.0" + +/* + * @offset: within EC_LPC_ADDR_MEMMAP region + * @bytes: number of bytes to read. zero means "read a string" (including '\0') + * (at most only EC_MEMMAP_SIZE bytes can be read) + * @buffer: where to store the result + * ioctl returns the number of bytes read, negative on error + */ +struct cros_ec_readmem { + uint32_t offset; + uint32_t bytes; + uint8_t buffer[EC_MEMMAP_SIZE]; +}; + +#define CROS_EC_DEV_IOC 0xEC +#define CROS_EC_DEV_IOCXCMD _IOWR(CROS_EC_DEV_IOC, 0, struct cros_ec_command) +#define CROS_EC_DEV_IOCRDMEM _IOWR(CROS_EC_DEV_IOC, 1, struct cros_ec_readmem) + +/* Lightbar utilities */ +extern bool ec_has_lightbar(struct cros_ec_dev *ec); +extern int lb_manual_suspend_ctrl(struct cros_ec_dev *ec, uint8_t enable); +extern int lb_suspend(struct cros_ec_dev *ec); +extern int lb_resume(struct cros_ec_dev *ec); + +#endif /* _CROS_EC_DEV_H_ */ diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c new file mode 100644 index 000000000000..5c858e784a89 --- /dev/null +++ b/drivers/mfd/rave-sp.c @@ -0,0 +1,710 @@ +// SPDX-License-Identifier: GPL-2.0+ + +/* + * Multifunction core driver for Zodiac Inflight Innovations RAVE + * Supervisory Processor(SP) MCU that is connected via dedicated UART + * port + * + * Copyright (C) 2017 Zodiac Inflight Innovations + */ + +#include <linux/atomic.h> +#include <linux/crc-ccitt.h> +#include <linux/delay.h> +#include <linux/export.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/mfd/rave-sp.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/sched.h> +#include <linux/serdev.h> +#include <asm/unaligned.h> + +/* + * UART protocol using following entities: + * - message to MCU => ACK response + * - event from MCU => event ACK + * + * Frame structure: + * <STX> <DATA> <CHECKSUM> <ETX> + * Where: + * - STX - is start of transmission character + * - ETX - end of transmission + * - DATA - payload + * - CHECKSUM - checksum calculated on <DATA> + * + * If <DATA> or <CHECKSUM> contain one of control characters, then it is + * escaped using <DLE> control code. Added <DLE> does not participate in + * checksum calculation. + */ +#define RAVE_SP_STX 0x02 +#define RAVE_SP_ETX 0x03 +#define RAVE_SP_DLE 0x10 + +#define RAVE_SP_MAX_DATA_SIZE 64 +#define RAVE_SP_CHECKSUM_SIZE 2 /* Worst case scenario on RDU2 */ +/* + * We don't store STX, ETX and unescaped bytes, so Rx is only + * DATA + CSUM + */ +#define RAVE_SP_RX_BUFFER_SIZE \ + (RAVE_SP_MAX_DATA_SIZE + RAVE_SP_CHECKSUM_SIZE) + +#define RAVE_SP_STX_ETX_SIZE 2 +/* + * For Tx we have to have space for everything, STX, EXT and + * potentially stuffed DATA + CSUM data + csum + */ +#define RAVE_SP_TX_BUFFER_SIZE \ + (RAVE_SP_STX_ETX_SIZE + 2 * RAVE_SP_RX_BUFFER_SIZE) + +#define RAVE_SP_BOOT_SOURCE_GET 0 +#define RAVE_SP_BOOT_SOURCE_SET 1 + +#define RAVE_SP_RDU2_BOARD_TYPE_RMB 0 +#define RAVE_SP_RDU2_BOARD_TYPE_DEB 1 + +#define RAVE_SP_BOOT_SOURCE_SD 0 +#define RAVE_SP_BOOT_SOURCE_EMMC 1 +#define RAVE_SP_BOOT_SOURCE_NOR 2 + +/** + * enum rave_sp_deframer_state - Possible state for de-framer + * + * @RAVE_SP_EXPECT_SOF: Scanning input for start-of-frame marker + * @RAVE_SP_EXPECT_DATA: Got start of frame marker, collecting frame + * @RAVE_SP_EXPECT_ESCAPED_DATA: Got escape character, collecting escaped byte + */ +enum rave_sp_deframer_state { + RAVE_SP_EXPECT_SOF, + RAVE_SP_EXPECT_DATA, + RAVE_SP_EXPECT_ESCAPED_DATA, +}; + +/** + * struct rave_sp_deframer - Device protocol deframer + * + * @state: Current state of the deframer + * @data: Buffer used to collect deframed data + * @length: Number of bytes de-framed so far + */ +struct rave_sp_deframer { + enum rave_sp_deframer_state state; + unsigned char data[RAVE_SP_RX_BUFFER_SIZE]; + size_t length; +}; + +/** + * struct rave_sp_reply - Reply as per RAVE device protocol + * + * @length: Expected reply length + * @data: Buffer to store reply payload in + * @code: Expected reply code + * @ackid: Expected reply ACK ID + * @completion: Successful reply reception completion + */ +struct rave_sp_reply { + size_t length; + void *data; + u8 code; + u8 ackid; + struct completion received; +}; + +/** + * struct rave_sp_checksum - Variant specific checksum implementation details + * + * @length: Caculated checksum length + * @subroutine: Utilized checksum algorithm implementation + */ +struct rave_sp_checksum { + size_t length; + void (*subroutine)(const u8 *, size_t, u8 *); +}; + +/** + * struct rave_sp_variant_cmds - Variant specific command routines + * + * @translate: Generic to variant specific command mapping routine + * + */ +struct rave_sp_variant_cmds { + int (*translate)(enum rave_sp_command); +}; + +/** + * struct rave_sp_variant - RAVE supervisory processor core variant + * + * @checksum: Variant specific checksum implementation + * @cmd: Variant specific command pointer table + * + */ +struct rave_sp_variant { + const struct rave_sp_checksum *checksum; + struct rave_sp_variant_cmds cmd; +}; + +/** + * struct rave_sp - RAVE supervisory processor core + * + * @serdev: Pointer to underlying serdev + * @deframer: Stored state of the protocol deframer + * @ackid: ACK ID used in last reply sent to the device + * @bus_lock: Lock to serialize access to the device + * @reply_lock: Lock protecting @reply + * @reply: Pointer to memory to store reply payload + * + * @variant: Device variant specific information + * @event_notifier_list: Input event notification chain + * + */ +struct rave_sp { + struct serdev_device *serdev; + struct rave_sp_deframer deframer; + atomic_t ackid; + struct mutex bus_lock; + struct mutex reply_lock; + struct rave_sp_reply *reply; + + const struct rave_sp_variant *variant; + struct blocking_notifier_head event_notifier_list; +}; + +static bool rave_sp_id_is_event(u8 code) +{ + return (code & 0xF0) == RAVE_SP_EVNT_BASE; +} + +static void rave_sp_unregister_event_notifier(struct device *dev, void *res) +{ + struct rave_sp *sp = dev_get_drvdata(dev->parent); + struct notifier_block *nb = *(struct notifier_block **)res; + struct blocking_notifier_head *bnh = &sp->event_notifier_list; + + WARN_ON(blocking_notifier_chain_unregister(bnh, nb)); +} + +int devm_rave_sp_register_event_notifier(struct device *dev, + struct notifier_block *nb) +{ + struct rave_sp *sp = dev_get_drvdata(dev->parent); + struct notifier_block **rcnb; + int ret; + + rcnb = devres_alloc(rave_sp_unregister_event_notifier, + sizeof(*rcnb), GFP_KERNEL); + if (!rcnb) + return -ENOMEM; + + ret = blocking_notifier_chain_register(&sp->event_notifier_list, nb); + if (!ret) { + *rcnb = nb; + devres_add(dev, rcnb); + } else { + devres_free(rcnb); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_rave_sp_register_event_notifier); + +static void csum_8b2c(const u8 *buf, size_t size, u8 *crc) +{ + *crc = *buf++; + size--; + + while (size--) + *crc += *buf++; + + *crc = 1 + ~(*crc); +} + +static void csum_ccitt(const u8 *buf, size_t size, u8 *crc) +{ + const u16 calculated = crc_ccitt_false(0xffff, buf, size); + + /* + * While the rest of the wire protocol is little-endian, + * CCITT-16 CRC in RDU2 device is sent out in big-endian order. + */ + put_unaligned_be16(calculated, crc); +} + +static void *stuff(unsigned char *dest, const unsigned char *src, size_t n) +{ + while (n--) { + const unsigned char byte = *src++; + + switch (byte) { + case RAVE_SP_STX: + case RAVE_SP_ETX: + case RAVE_SP_DLE: + *dest++ = RAVE_SP_DLE; + /* FALLTHROUGH */ + default: + *dest++ = byte; + } + } + + return dest; +} + +static int rave_sp_write(struct rave_sp *sp, const u8 *data, u8 data_size) +{ + const size_t checksum_length = sp->variant->checksum->length; + unsigned char frame[RAVE_SP_TX_BUFFER_SIZE]; + unsigned char crc[RAVE_SP_CHECKSUM_SIZE]; + unsigned char *dest = frame; + size_t length; + + if (WARN_ON(checksum_length > sizeof(crc))) + return -ENOMEM; + + if (WARN_ON(data_size > sizeof(frame))) + return -ENOMEM; + + sp->variant->checksum->subroutine(data, data_size, crc); + + *dest++ = RAVE_SP_STX; + dest = stuff(dest, data, data_size); + dest = stuff(dest, crc, checksum_length); + *dest++ = RAVE_SP_ETX; + + length = dest - frame; + + print_hex_dump(KERN_DEBUG, "rave-sp tx: ", DUMP_PREFIX_NONE, + 16, 1, frame, length, false); + + return serdev_device_write(sp->serdev, frame, length, HZ); +} + +static u8 rave_sp_reply_code(u8 command) +{ + /* + * There isn't a single rule that describes command code -> + * ACK code transformation, but, going through various + * versions of ICDs, there appear to be three distinct groups + * that can be described by simple transformation. + */ + switch (command) { + case 0xA0 ... 0xBE: + /* + * Commands implemented by firmware found in RDU1 and + * older devices all seem to obey the following rule + */ + return command + 0x20; + case 0xE0 ... 0xEF: + /* + * Events emitted by all versions of the firmare use + * least significant bit to get an ACK code + */ + return command | 0x01; + default: + /* + * Commands implemented by firmware found in RDU2 are + * similar to "old" commands, but they use slightly + * different offset + */ + return command + 0x40; + } +} + +int rave_sp_exec(struct rave_sp *sp, + void *__data, size_t data_size, + void *reply_data, size_t reply_data_size) +{ + struct rave_sp_reply reply = { + .data = reply_data, + .length = reply_data_size, + .received = COMPLETION_INITIALIZER_ONSTACK(reply.received), + }; + unsigned char *data = __data; + int command, ret = 0; + u8 ackid; + + command = sp->variant->cmd.translate(data[0]); + if (command < 0) + return command; + + ackid = atomic_inc_return(&sp->ackid); + reply.ackid = ackid; + reply.code = rave_sp_reply_code((u8)command), + + mutex_lock(&sp->bus_lock); + + mutex_lock(&sp->reply_lock); + sp->reply = &reply; + mutex_unlock(&sp->reply_lock); + + data[0] = command; + data[1] = ackid; + + rave_sp_write(sp, data, data_size); + + if (!wait_for_completion_timeout(&reply.received, HZ)) { + dev_err(&sp->serdev->dev, "Command timeout\n"); + ret = -ETIMEDOUT; + + mutex_lock(&sp->reply_lock); + sp->reply = NULL; + mutex_unlock(&sp->reply_lock); + } + + mutex_unlock(&sp->bus_lock); + return ret; +} +EXPORT_SYMBOL_GPL(rave_sp_exec); + +static void rave_sp_receive_event(struct rave_sp *sp, + const unsigned char *data, size_t length) +{ + u8 cmd[] = { + [0] = rave_sp_reply_code(data[0]), + [1] = data[1], + }; + + rave_sp_write(sp, cmd, sizeof(cmd)); + + blocking_notifier_call_chain(&sp->event_notifier_list, + rave_sp_action_pack(data[0], data[2]), + NULL); +} + +static void rave_sp_receive_reply(struct rave_sp *sp, + const unsigned char *data, size_t length) +{ + struct device *dev = &sp->serdev->dev; + struct rave_sp_reply *reply; + const size_t payload_length = length - 2; + + mutex_lock(&sp->reply_lock); + reply = sp->reply; + + if (reply) { + if (reply->code == data[0] && reply->ackid == data[1] && + payload_length >= reply->length) { + /* + * We are relying on memcpy(dst, src, 0) to be a no-op + * when handling commands that have a no-payload reply + */ + memcpy(reply->data, &data[2], reply->length); + complete(&reply->received); + sp->reply = NULL; + } else { + dev_err(dev, "Ignoring incorrect reply\n"); + dev_dbg(dev, "Code: expected = 0x%08x received = 0x%08x\n", + reply->code, data[0]); + dev_dbg(dev, "ACK ID: expected = 0x%08x received = 0x%08x\n", + reply->ackid, data[1]); + dev_dbg(dev, "Length: expected = %zu received = %zu\n", + reply->length, payload_length); + } + } + + mutex_unlock(&sp->reply_lock); +} + +static void rave_sp_receive_frame(struct rave_sp *sp, + const unsigned char *data, + size_t length) +{ + const size_t checksum_length = sp->variant->checksum->length; + const size_t payload_length = length - checksum_length; + const u8 *crc_reported = &data[payload_length]; + struct device *dev = &sp->serdev->dev; + u8 crc_calculated[checksum_length]; + + print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE, + 16, 1, data, length, false); + + if (unlikely(length <= checksum_length)) { + dev_warn(dev, "Dropping short frame\n"); + return; + } + + sp->variant->checksum->subroutine(data, payload_length, + crc_calculated); + + if (memcmp(crc_calculated, crc_reported, checksum_length)) { + dev_warn(dev, "Dropping bad frame\n"); + return; + } + + if (rave_sp_id_is_event(data[0])) + rave_sp_receive_event(sp, data, length); + else + rave_sp_receive_reply(sp, data, length); +} + +static int rave_sp_receive_buf(struct serdev_device *serdev, + const unsigned char *buf, size_t size) +{ + struct device *dev = &serdev->dev; + struct rave_sp *sp = dev_get_drvdata(dev); + struct rave_sp_deframer *deframer = &sp->deframer; + const unsigned char *src = buf; + const unsigned char *end = buf + size; + + while (src < end) { + const unsigned char byte = *src++; + + switch (deframer->state) { + case RAVE_SP_EXPECT_SOF: + if (byte == RAVE_SP_STX) + deframer->state = RAVE_SP_EXPECT_DATA; + break; + + case RAVE_SP_EXPECT_DATA: + /* + * Treat special byte values first + */ + switch (byte) { + case RAVE_SP_ETX: + rave_sp_receive_frame(sp, + deframer->data, + deframer->length); + /* + * Once we extracted a complete frame + * out of a stream, we call it done + * and proceed to bailing out while + * resetting the framer to initial + * state, regardless if we've consumed + * all of the stream or not. + */ + goto reset_framer; + case RAVE_SP_STX: + dev_warn(dev, "Bad frame: STX before ETX\n"); + /* + * If we encounter second "start of + * the frame" marker before seeing + * corresponding "end of frame", we + * reset the framer and ignore both: + * frame started by first SOF and + * frame started by current SOF. + * + * NOTE: The above means that only the + * frame started by third SOF, sent + * after this one will have a chance + * to get throught. + */ + goto reset_framer; + case RAVE_SP_DLE: + deframer->state = RAVE_SP_EXPECT_ESCAPED_DATA; + /* + * If we encounter escape sequence we + * need to skip it and collect the + * byte that follows. We do it by + * forcing the next iteration of the + * encompassing while loop. + */ + continue; + } + /* + * For the rest of the bytes, that are not + * speical snoflakes, we do the same thing + * that we do to escaped data - collect it in + * deframer buffer + */ + + /* FALLTHROUGH */ + + case RAVE_SP_EXPECT_ESCAPED_DATA: + deframer->data[deframer->length++] = byte; + + if (deframer->length == sizeof(deframer->data)) { + dev_warn(dev, "Bad frame: Too long\n"); + /* + * If the amount of data we've + * accumulated for current frame so + * far starts to exceed the capacity + * of deframer's buffer, there's + * nothing else we can do but to + * discard that data and start + * assemblying a new frame again + */ + goto reset_framer; + } + + /* + * We've extracted out special byte, now we + * can go back to regular data collecting + */ + deframer->state = RAVE_SP_EXPECT_DATA; + break; + } + } + + /* + * The only way to get out of the above loop and end up here + * is throught consuming all of the supplied data, so here we + * report that we processed it all. + */ + return size; + +reset_framer: + /* + * NOTE: A number of codepaths that will drop us here will do + * so before consuming all 'size' bytes of the data passed by + * serdev layer. We rely on the fact that serdev layer will + * re-execute this handler with the remainder of the Rx bytes + * once we report actual number of bytes that we processed. + */ + deframer->state = RAVE_SP_EXPECT_SOF; + deframer->length = 0; + + return src - buf; +} + +static int rave_sp_rdu1_cmd_translate(enum rave_sp_command command) +{ + if (command >= RAVE_SP_CMD_STATUS && + command <= RAVE_SP_CMD_CONTROL_EVENTS) + return command; + + return -EINVAL; +} + +static int rave_sp_rdu2_cmd_translate(enum rave_sp_command command) +{ + if (command >= RAVE_SP_CMD_GET_FIRMWARE_VERSION && + command <= RAVE_SP_CMD_GET_GPIO_STATE) + return command; + + if (command == RAVE_SP_CMD_REQ_COPPER_REV) { + /* + * As per RDU2 ICD 3.4.47 CMD_GET_COPPER_REV code is + * different from that for RDU1 and it is set to 0x28. + */ + return 0x28; + } + + return rave_sp_rdu1_cmd_translate(command); +} + +static int rave_sp_default_cmd_translate(enum rave_sp_command command) +{ + /* + * All of the following command codes were taken from "Table : + * Communications Protocol Message Types" in section 3.3 + * "MESSAGE TYPES" of Rave PIC24 ICD. + */ + switch (command) { + case RAVE_SP_CMD_GET_FIRMWARE_VERSION: + return 0x11; + case RAVE_SP_CMD_GET_BOOTLOADER_VERSION: + return 0x12; + case RAVE_SP_CMD_BOOT_SOURCE: + return 0x14; + case RAVE_SP_CMD_SW_WDT: + return 0x1C; + case RAVE_SP_CMD_RESET: + return 0x1E; + case RAVE_SP_CMD_RESET_REASON: + return 0x1F; + default: + return -EINVAL; + } +} + +static const struct rave_sp_checksum rave_sp_checksum_8b2c = { + .length = 1, + .subroutine = csum_8b2c, +}; + +static const struct rave_sp_checksum rave_sp_checksum_ccitt = { + .length = 2, + .subroutine = csum_ccitt, +}; + +static const struct rave_sp_variant rave_sp_legacy = { + .checksum = &rave_sp_checksum_8b2c, + .cmd = { + .translate = rave_sp_default_cmd_translate, + }, +}; + +static const struct rave_sp_variant rave_sp_rdu1 = { + .checksum = &rave_sp_checksum_8b2c, + .cmd = { + .translate = rave_sp_rdu1_cmd_translate, + }, +}; + +static const struct rave_sp_variant rave_sp_rdu2 = { + .checksum = &rave_sp_checksum_ccitt, + .cmd = { + .translate = rave_sp_rdu2_cmd_translate, + }, +}; + +static const struct of_device_id rave_sp_dt_ids[] = { + { .compatible = "zii,rave-sp-niu", .data = &rave_sp_legacy }, + { .compatible = "zii,rave-sp-mezz", .data = &rave_sp_legacy }, + { .compatible = "zii,rave-sp-esb", .data = &rave_sp_legacy }, + { .compatible = "zii,rave-sp-rdu1", .data = &rave_sp_rdu1 }, + { .compatible = "zii,rave-sp-rdu2", .data = &rave_sp_rdu2 }, + { /* sentinel */ } +}; + +static const struct serdev_device_ops rave_sp_serdev_device_ops = { + .receive_buf = rave_sp_receive_buf, + .write_wakeup = serdev_device_write_wakeup, +}; + +static int rave_sp_probe(struct serdev_device *serdev) +{ + struct device *dev = &serdev->dev; + struct rave_sp *sp; + u32 baud; + int ret; + + if (of_property_read_u32(dev->of_node, "current-speed", &baud)) { + dev_err(dev, + "'current-speed' is not specified in device node\n"); + return -EINVAL; + } + + sp = devm_kzalloc(dev, sizeof(*sp), GFP_KERNEL); + if (!sp) + return -ENOMEM; + + sp->serdev = serdev; + dev_set_drvdata(dev, sp); + + sp->variant = of_device_get_match_data(dev); + if (!sp->variant) + return -ENODEV; + + mutex_init(&sp->bus_lock); + mutex_init(&sp->reply_lock); + BLOCKING_INIT_NOTIFIER_HEAD(&sp->event_notifier_list); + + serdev_device_set_client_ops(serdev, &rave_sp_serdev_device_ops); + ret = devm_serdev_device_open(dev, serdev); + if (ret) + return ret; + + serdev_device_set_baudrate(serdev, baud); + + return devm_of_platform_populate(dev); +} + +MODULE_DEVICE_TABLE(of, rave_sp_dt_ids); + +static struct serdev_device_driver rave_sp_drv = { + .probe = rave_sp_probe, + .driver = { + .name = "rave-sp", + .of_match_table = rave_sp_dt_ids, + }, +}; +module_serdev_device_driver(rave_sp_drv); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>"); +MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>"); +MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>"); +MODULE_DESCRIPTION("RAVE SP core driver"); |