diff options
| -rw-r--r-- | MAINTAINERS | 9 | ||||
| -rw-r--r-- | drivers/gpio/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/gpio/Makefile | 1 | ||||
| -rw-r--r-- | drivers/gpio/gpio-cgbc.c | 196 | ||||
| -rw-r--r-- | drivers/i2c/busses/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/i2c/busses/Makefile | 1 | ||||
| -rw-r--r-- | drivers/i2c/busses/i2c-cgbc.c | 406 | ||||
| -rw-r--r-- | drivers/mfd/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/mfd/Makefile | 1 | ||||
| -rw-r--r-- | drivers/mfd/cgbc-core.c | 411 | ||||
| -rw-r--r-- | drivers/watchdog/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/watchdog/Makefile | 1 | ||||
| -rw-r--r-- | drivers/watchdog/cgbc_wdt.c | 211 | ||||
| -rw-r--r-- | include/linux/mfd/cgbc.h | 44 |
14 files changed, 1323 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index c27f3190737f..6f218022bd02 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5760,6 +5760,15 @@ F: fs/configfs/ F: include/linux/configfs.h F: samples/configfs/ +CONGATEC BOARD CONTROLLER MFD DRIVER +M: Thomas Richard <thomas.richard@bootlin.com> +S: Maintained +F: drivers/gpio/gpio-cgbc.c +F: drivers/i2c/busses/i2c-cgbc.c +F: drivers/mfd/cgbc-core.c +F: drivers/watchdog/cgbc_wdt.c +F: include/linux/mfd/cgbc.h + CONSOLE SUBSYSTEM M: Greg Kroah-Hartman <gregkh@linuxfoundation.org> S: Supported diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 33215ea29d69..bfa6b5a2c537 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -1286,6 +1286,16 @@ config GPIO_BD9571MWV This driver can also be built as a module. If so, the module will be called gpio-bd9571mwv. +config GPIO_CGBC + tristate "Congatec Board Controller GPIO support" + depends on MFD_CGBC + help + Select this option to enable GPIO support for the Congatec Board + Controller. + + This driver can also be built as a module. If so, the module will be + called gpio-cgbc. + config GPIO_CROS_EC tristate "ChromeOS EC GPIO support" depends on CROS_EC diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 1429e8c0229b..3cdfa927ed98 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -45,6 +45,7 @@ obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o obj-$(CONFIG_GPIO_CADENCE) += gpio-cadence.o +obj-$(CONFIG_GPIO_CGBC) += gpio-cgbc.o obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o obj-$(CONFIG_GPIO_SNPS_CREG) += gpio-creg-snps.o obj-$(CONFIG_GPIO_CROS_EC) += gpio-cros-ec.o diff --git a/drivers/gpio/gpio-cgbc.c b/drivers/gpio/gpio-cgbc.c new file mode 100644 index 000000000000..9213faa11522 --- /dev/null +++ b/drivers/gpio/gpio-cgbc.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Congatec Board Controller GPIO driver + * + * Copyright (C) 2024 Bootlin + * Author: Thomas Richard <thomas.richard@bootlin.com> + */ + +#include <linux/gpio/driver.h> +#include <linux/mfd/cgbc.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> + +#define CGBC_GPIO_NGPIO 14 + +#define CGBC_GPIO_CMD_GET 0x64 +#define CGBC_GPIO_CMD_SET 0x65 +#define CGBC_GPIO_CMD_DIR_GET 0x66 +#define CGBC_GPIO_CMD_DIR_SET 0x67 + +struct cgbc_gpio_data { + struct gpio_chip chip; + struct cgbc_device_data *cgbc; + struct mutex lock; +}; + +static int cgbc_gpio_cmd(struct cgbc_device_data *cgbc, + u8 cmd0, u8 cmd1, u8 cmd2, u8 *value) +{ + u8 cmd[3] = {cmd0, cmd1, cmd2}; + + return cgbc_command(cgbc, cmd, sizeof(cmd), value, 1, NULL); +} + +static int cgbc_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + struct cgbc_device_data *cgbc = gpio->cgbc; + int ret; + u8 val; + + scoped_guard(mutex, &gpio->lock) + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_GET, (offset > 7) ? 1 : 0, 0, &val); + + offset %= 8; + + if (ret) + return ret; + else + return (int)(val & (u8)BIT(offset)); +} + +static void __cgbc_gpio_set(struct gpio_chip *chip, + unsigned int offset, int value) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + struct cgbc_device_data *cgbc = gpio->cgbc; + u8 val; + int ret; + + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_GET, (offset > 7) ? 1 : 0, 0, &val); + if (ret) + return; + + if (value) + val |= BIT(offset % 8); + else + val &= ~(BIT(offset % 8)); + + cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_SET, (offset > 7) ? 1 : 0, val, &val); +} + +static void cgbc_gpio_set(struct gpio_chip *chip, + unsigned int offset, int value) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + + scoped_guard(mutex, &gpio->lock) + __cgbc_gpio_set(chip, offset, value); +} + +static int cgbc_gpio_direction_set(struct gpio_chip *chip, + unsigned int offset, int direction) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + struct cgbc_device_data *cgbc = gpio->cgbc; + int ret; + u8 val; + + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_DIR_GET, (offset > 7) ? 1 : 0, 0, &val); + if (ret) + goto end; + + if (direction == GPIO_LINE_DIRECTION_IN) + val &= ~(BIT(offset % 8)); + else + val |= BIT(offset % 8); + + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_DIR_SET, (offset > 7) ? 1 : 0, val, &val); + +end: + return ret; +} + +static int cgbc_gpio_direction_input(struct gpio_chip *chip, + unsigned int offset) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + + guard(mutex)(&gpio->lock); + return cgbc_gpio_direction_set(chip, offset, GPIO_LINE_DIRECTION_IN); +} + +static int cgbc_gpio_direction_output(struct gpio_chip *chip, + unsigned int offset, int value) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + + guard(mutex)(&gpio->lock); + + __cgbc_gpio_set(chip, offset, value); + return cgbc_gpio_direction_set(chip, offset, GPIO_LINE_DIRECTION_OUT); +} + +static int cgbc_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) +{ + struct cgbc_gpio_data *gpio = gpiochip_get_data(chip); + struct cgbc_device_data *cgbc = gpio->cgbc; + int ret; + u8 val; + + scoped_guard(mutex, &gpio->lock) + ret = cgbc_gpio_cmd(cgbc, CGBC_GPIO_CMD_DIR_GET, (offset > 7) ? 1 : 0, 0, &val); + + if (ret) + return ret; + + if (val & BIT(offset % 8)) + return GPIO_LINE_DIRECTION_OUT; + else + return GPIO_LINE_DIRECTION_IN; +} + +static int cgbc_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct cgbc_device_data *cgbc = dev_get_drvdata(dev->parent); + struct cgbc_gpio_data *gpio; + struct gpio_chip *chip; + int ret; + + gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL); + if (!gpio) + return -ENOMEM; + + gpio->cgbc = cgbc; + + platform_set_drvdata(pdev, gpio); + + chip = &gpio->chip; + chip->label = dev_name(&pdev->dev); + chip->owner = THIS_MODULE; + chip->parent = dev; + chip->base = -1; + chip->direction_input = cgbc_gpio_direction_input; + chip->direction_output = cgbc_gpio_direction_output; + chip->get_direction = cgbc_gpio_get_direction; + chip->get = cgbc_gpio_get; + chip->set = cgbc_gpio_set; + chip->ngpio = CGBC_GPIO_NGPIO; + + ret = devm_mutex_init(dev, &gpio->lock); + if (ret) + return ret; + + ret = devm_gpiochip_add_data(dev, chip, gpio); + if (ret) + return dev_err_probe(dev, ret, "Could not register GPIO chip\n"); + + return 0; +} + +static struct platform_driver cgbc_gpio_driver = { + .driver = { + .name = "cgbc-gpio", + }, + .probe = cgbc_gpio_probe, +}; + +module_platform_driver(cgbc_gpio_driver); + +MODULE_DESCRIPTION("Congatec Board Controller GPIO Driver"); +MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:cgbc-gpio"); diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 6b3ba7e5723a..4977abcd7c46 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -535,6 +535,16 @@ config I2C_CBUS_GPIO This driver can also be built as a module. If so, the module will be called i2c-cbus-gpio. +config I2C_CGBC + tristate "Congatec I2C Controller" + depends on MFD_CGBC + help + This driver supports the 2 I2C interfaces on the Congatec Board + Controller. + + This driver can also be built as a module. If so, the module will + be called i2c-cgbc.ko. + config I2C_CPM tristate "Freescale CPM1 or CPM2 (MPC8xx/826x)" depends on CPM1 || CPM2 diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index ecc07c50f2a0..a6bcbf2febcf 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -50,6 +50,7 @@ obj-$(CONFIG_I2C_BCM2835) += i2c-bcm2835.o obj-$(CONFIG_I2C_BCM_IPROC) += i2c-bcm-iproc.o obj-$(CONFIG_I2C_CADENCE) += i2c-cadence.o obj-$(CONFIG_I2C_CBUS_GPIO) += i2c-cbus-gpio.o +obj-$(CONFIG_I2C_CGBC) += i2c-cgbc.o obj-$(CONFIG_I2C_CPM) += i2c-cpm.o obj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o obj-$(CONFIG_I2C_DESIGNWARE_CORE) += i2c-designware-core.o diff --git a/drivers/i2c/busses/i2c-cgbc.c b/drivers/i2c/busses/i2c-cgbc.c new file mode 100644 index 000000000000..eba0b205de11 --- /dev/null +++ b/drivers/i2c/busses/i2c-cgbc.c @@ -0,0 +1,406 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Congatec Board Controller I2C busses driver + * + * Copyright (C) 2024 Bootlin + * Author: Thomas Richard <thomas.richard@bootlin.com> + */ + +#include <linux/i2c.h> +#include <linux/iopoll.h> +#include <linux/mfd/cgbc.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#define CGBC_I2C_PRIMARY_BUS_ID 0 +#define CGBC_I2C_PM_BUS_ID 4 + +#define CGBC_I2C_CMD_START 0x40 +#define CGBC_I2C_CMD_STAT 0x48 +#define CGBC_I2C_CMD_DATA 0x50 +#define CGBC_I2C_CMD_SPEED 0x58 + +#define CGBC_I2C_STAT_IDL 0x00 +#define CGBC_I2C_STAT_DAT 0x01 +#define CGBC_I2C_STAT_BUSY 0x02 + +#define CGBC_I2C_START 0x80 +#define CGBC_I2C_STOP 0x40 + +#define CGBC_I2C_LAST_ACK 0x80 /* send ACK on last read byte */ + +/* + * Reference code defines 1kHz as min freq and 6.1MHz as max freq. + * But in practice, the board controller limits the frequency to 1MHz, and the + * 1kHz is not functional (minimal working freq is 50kHz). + * So use these values as limits. + */ +#define CGBC_I2C_FREQ_MIN_HZ 50000 /* 50 kHz */ +#define CGBC_I2C_FREQ_MAX_HZ 1000000 /* 1 MHz */ + +#define CGBC_I2C_FREQ_UNIT_1KHZ 0x40 +#define CGBC_I2C_FREQ_UNIT_10KHZ 0x80 +#define CGBC_I2C_FREQ_UNIT_100KHZ 0xC0 + +#define CGBC_I2C_FREQ_UNIT_MASK 0xC0 +#define CGBC_I2C_FREQ_VALUE_MASK 0x3F + +#define CGBC_I2C_READ_MAX_LEN 31 +#define CGBC_I2C_WRITE_MAX_LEN 32 + +#define CGBC_I2C_CMD_HEADER_SIZE 4 +#define CGBC_I2C_CMD_SIZE (CGBC_I2C_CMD_HEADER_SIZE + CGBC_I2C_WRITE_MAX_LEN) + +enum cgbc_i2c_state { + CGBC_I2C_STATE_DONE = 0, + CGBC_I2C_STATE_INIT, + CGBC_I2C_STATE_START, + CGBC_I2C_STATE_READ, + CGBC_I2C_STATE_WRITE, + CGBC_I2C_STATE_ERROR, +}; + +struct i2c_algo_cgbc_data { + u8 bus_id; + unsigned long read_maxtime_us; +}; + +struct cgbc_i2c_data { + struct device *dev; + struct cgbc_device_data *cgbc; + struct i2c_adapter adap; + struct i2c_msg *msg; + int nmsgs; + int pos; + enum cgbc_i2c_state state; +}; + +struct cgbc_i2c_transfer { + u8 bus_id; + bool start; + bool stop; + bool last_ack; + u8 read; + u8 write; + u8 addr; + u8 data[CGBC_I2C_WRITE_MAX_LEN]; +}; + +static u8 cgbc_i2c_freq_to_reg(unsigned int bus_frequency) +{ + u8 reg; + + if (bus_frequency <= 10000) + reg = CGBC_I2C_FREQ_UNIT_1KHZ | (bus_frequency / 1000); + else if (bus_frequency <= 100000) + reg = CGBC_I2C_FREQ_UNIT_10KHZ | (bus_frequency / 10000); + else + reg = CGBC_I2C_FREQ_UNIT_100KHZ | (bus_frequency / 100000); + + return reg; +} + +static unsigned int cgbc_i2c_reg_to_freq(u8 reg) +{ + unsigned int freq = reg & CGBC_I2C_FREQ_VALUE_MASK; + u8 unit = reg & CGBC_I2C_FREQ_UNIT_MASK; + + if (unit == CGBC_I2C_FREQ_UNIT_100KHZ) + return freq * 100000; + else if (unit == CGBC_I2C_FREQ_UNIT_10KHZ) + return freq * 10000; + else + return freq * 1000; +} + +static int cgbc_i2c_get_status(struct i2c_adapter *adap) +{ + struct i2c_algo_cgbc_data *algo_data = adap->algo_data; + struct cgbc_i2c_data *i2c = i2c_get_adapdata(adap); + struct cgbc_device_data *cgbc = i2c->cgbc; + u8 cmd = CGBC_I2C_CMD_STAT | algo_data->bus_id; + u8 status; + int ret; + + ret = cgbc_command(cgbc, &cmd, sizeof(cmd), NULL, 0, &status); + if (ret) + return ret; + + return status; +} + +static int cgbc_i2c_set_frequency(struct i2c_adapter *adap, + unsigned int bus_frequency) +{ + struct i2c_algo_cgbc_data *algo_data = adap->algo_data; + struct cgbc_i2c_data *i2c = i2c_get_adapdata(adap); + struct cgbc_device_data *cgbc = i2c->cgbc; + u8 cmd[2], data; + int ret; + + if (bus_frequency > CGBC_I2C_FREQ_MAX_HZ || + bus_frequency < CGBC_I2C_FREQ_MIN_HZ) { + dev_info(i2c->dev, "invalid frequency %u, using default\n", bus_frequency); + bus_frequency = I2C_MAX_STANDARD_MODE_FREQ; + } + + cmd[0] = CGBC_I2C_CMD_SPEED | algo_data->bus_id; + cmd[1] = cgbc_i2c_freq_to_reg(bus_frequency); + + ret = cgbc_command(cgbc, &cmd, sizeof(cmd), &data, 1, NULL); + if (ret) + return dev_err_probe(i2c->dev, ret, + "Failed to initialize I2C bus %s", + adap->name); + + cmd[1] = 0x00; + + ret = cgbc_command(cgbc, &cmd, sizeof(cmd), &data, 1, NULL); + if (ret) + return dev_err_probe(i2c->dev, ret, + "Failed to get I2C bus frequency"); + + bus_frequency = cgbc_i2c_reg_to_freq(data); + + dev_dbg(i2c->dev, "%s is running at %d Hz\n", adap->name, bus_frequency); + + /* + * The read_maxtime_us variable represents the maximum time to wait + * for data during a read operation. The maximum amount of data that + * can be read by a command is CGBC_I2C_READ_MAX_LEN. + * Therefore, calculate the max time to properly size the timeout. + */ + algo_data->read_maxtime_us = (BITS_PER_BYTE + 1) * CGBC_I2C_READ_MAX_LEN + * USEC_PER_SEC / bus_frequency; + + return 0; +} + +static unsigned int cgbc_i2c_xfer_to_cmd(struct cgbc_i2c_transfer xfer, u8 *cmd) +{ + int i = 0; + + cmd[i++] = CGBC_I2C_CMD_START | xfer.bus_id; + + cmd[i] = (xfer.start) ? CGBC_I2C_START : 0x00; + if (xfer.stop) + cmd[i] |= CGBC_I2C_STOP; + cmd[i++] |= (xfer.start) ? xfer.write + 1 : xfer.write; + + cmd[i++] = (xfer.last_ack) ? (xfer.read | CGBC_I2C_LAST_ACK) : xfer.read; + + if (xfer.start) + cmd[i++] = xfer.addr; + + if (xfer.write > 0) + memcpy(&cmd[i], &xfer.data, xfer.write); + + return i + xfer.write; +} + +static int cgbc_i2c_xfer_msg(struct i2c_adapter *adap) +{ + struct i2c_algo_cgbc_data *algo_data = adap->algo_data; + struct cgbc_i2c_data *i2c = i2c_get_adapdata(adap); + struct cgbc_device_data *cgbc = i2c->cgbc; + struct i2c_msg *msg = i2c->msg; + u8 cmd[CGBC_I2C_CMD_SIZE]; + int ret, max_len, len, i; + unsigned int cmd_len; + u8 cmd_data; + + struct cgbc_i2c_transfer xfer = { + .bus_id = algo_data->bus_id, + .addr = i2c_8bit_addr_from_msg(msg), + }; + + if (i2c->state == CGBC_I2C_STATE_DONE) + return 0; + + ret = cgbc_i2c_get_status(adap); + + if (ret == CGBC_I2C_STAT_BUSY) + return -EBUSY; + else if (ret < 0) + goto err; + + if (i2c->state == CGBC_I2C_STATE_INIT || + (i2c->state == CGBC_I2C_STATE_WRITE && msg->flags & I2C_M_RD)) + xfer.start = true; + + i2c->state = (msg->flags & I2C_M_RD) ? CGBC_I2C_STATE_READ : CGBC_I2C_STATE_WRITE; + + max_len = (i2c->state == CGBC_I2C_STATE_READ) ? + CGBC_I2C_READ_MAX_LEN : CGBC_I2C_WRITE_MAX_LEN; + + if (msg->len - i2c->pos > max_len) { + len = max_len; + } else { + len = msg->len - i2c->pos; + + if (i2c->nmsgs == 1) + xfer.stop = true; + } + + if (i2c->state == CGBC_I2C_STATE_WRITE) { + xfer.write = len; + xfer.read = 0; + + for (i = 0; i < len; i++) + xfer.data[i] = msg->buf[i2c->pos + i]; + + cmd_len = cgbc_i2c_xfer_to_cmd(xfer, &cmd[0]); + + ret = cgbc_command(cgbc, &cmd, cmd_len, NULL, 0, NULL); + if (ret) + goto err; + } else if (i2c->state == CGBC_I2C_STATE_READ) { + xfer.write = 0; + xfer.read = len; + + if (i2c->nmsgs > 1 || msg->len - i2c->pos > max_len) + xfer.read |= CGBC_I2C_LAST_ACK; + + cmd_len = cgbc_i2c_xfer_to_cmd(xfer, &cmd[0]); + ret = cgbc_command(cgbc, &cmd, cmd_len, NULL, 0, NULL); + if (ret) + goto err; + + ret = read_poll_timeout(cgbc_i2c_get_status, ret, + ret != CGBC_I2C_STAT_BUSY, 0, + 2 * algo_data->read_maxtime_us, false, adap); + if (ret < 0) + goto err; + + cmd_data = CGBC_I2C_CMD_DATA | algo_data->bus_id; + ret = cgbc_command(cgbc, &cmd_data, sizeof(cmd_data), + msg->buf + i2c->pos, len, NULL); + if (ret) + goto err; + } + + if (len == (msg->len - i2c->pos)) { + i2c->msg++; + i2c->nmsgs--; + i2c->pos = 0; + } else { + i2c->pos += len; + } + + if (i2c->nmsgs == 0) + i2c->state = CGBC_I2C_STATE_DONE; + + return 0; + +err: + i2c->state = CGBC_I2C_STATE_ERROR; + return ret; +} + +static int cgbc_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct cgbc_i2c_data *i2c = i2c_get_adapdata(adap); + unsigned long timeout = jiffies + HZ; + int ret; + + i2c->state = CGBC_I2C_STATE_INIT; + i2c->msg = msgs; + i2c->nmsgs = num; + i2c->pos = 0; + + while (time_before(jiffies, timeout)) { + ret = cgbc_i2c_xfer_msg(adap); + if (i2c->state == CGBC_I2C_STATE_DONE) + return num; + + if (i2c->state == CGBC_I2C_STATE_ERROR) + return ret; + + if (ret == 0) + timeout = jiffies + HZ; + } + + i2c->state = CGBC_I2C_STATE_ERROR; + return -ETIMEDOUT; +} + +static u32 cgbc_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~(I2C_FUNC_SMBUS_QUICK)); +} + +static const struct i2c_algorithm cgbc_i2c_algorithm = { + .master_xfer = cgbc_i2c_xfer, + .functionality = cgbc_i2c_func, +}; + +static struct i2c_algo_cgbc_data cgbc_i2c_algo_data[] = { + { .bus_id = CGBC_I2C_PRIMARY_BUS_ID }, + { .bus_id = CGBC_I2C_PM_BUS_ID }, +}; + +static const struct i2c_adapter cgbc_i2c_adapter[] = { + { + .owner = THIS_MODULE, + .name = "Congatec General Purpose I2C adapter", + .class = I2C_CLASS_DEPRECATED, + .algo = &cgbc_i2c_algorithm, + .algo_data = &cgbc_i2c_algo_data[0], + .nr = -1, + }, + { + .owner = THIS_MODULE, + .name = "Congatec Power Management I2C adapter", + .class = I2C_CLASS_DEPRECATED, + .algo = &cgbc_i2c_algorithm, + .algo_data = &cgbc_i2c_algo_data[1], + .nr = -1, + }, +}; + +static int cgbc_i2c_probe(struct platform_device *pdev) +{ + struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent); + struct cgbc_i2c_data *i2c; + int ret; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->cgbc = cgbc; + i2c->dev = &pdev->dev; + i2c->adap = cgbc_i2c_adapter[pdev->id]; + i2c->adap.dev.parent = i2c->dev; + i2c_set_adapdata(&i2c->adap, i2c); + platform_set_drvdata(pdev, i2c); + + ret = cgbc_i2c_set_frequency(&i2c->adap, I2C_MAX_STANDARD_MODE_FREQ); + if (ret) + return ret; + + return i2c_add_numbered_adapter(&i2c->adap); +} + +static void cgbc_i2c_remove(struct platform_device *pdev) +{ + struct cgbc_i2c_data *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); +} + +static struct platform_driver cgbc_i2c_driver = { + .driver = { + .name = "cgbc-i2c", + }, + .probe = cgbc_i2c_probe, + .remove_new = cgbc_i2c_remove, +}; + +module_platform_driver(cgbc_i2c_driver); + +MODULE_DESCRIPTION("Congatec Board Controller I2C Driver"); +MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:cgbc_i2c"); diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index f9325bcce1b9..03c1e4e3eea4 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -236,6 +236,18 @@ config MFD_AXP20X_RSB components like regulators or the PEK (Power Enable Key) under the corresponding menus. +config MFD_CGBC + tristate "Congatec Board Controller" + select MFD_CORE + depends on X86 + help + This is the core driver of the Board Controller found on some Congatec + SMARC modules. The Board Controller provides functions like watchdog, + I2C busses, and GPIO controller. + + To compile this driver as a module, choose M here: the module will be + called cgbc-core. + config MFD_CROS_EC_DEV tristate "ChromeOS Embedded Controller multifunction device" select MFD_CORE diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index 2a9f91e81af8..e057d6d6faef 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_MFD_SM501) += sm501.o obj-$(CONFIG_ARCH_BCM2835) += bcm2835-pm.o obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o obj-$(CONFIG_MFD_BD9571MWV) += bd9571mwv.o +obj-$(CONFIG_MFD_CGBC) += cgbc-core.o obj-$(CONFIG_MFD_CROS_EC_DEV) += cros_ec_dev.o obj-$(CONFIG_MFD_CS42L43) += cs42l43.o obj-$(CONFIG_MFD_CS42L43_I2C) += cs42l43-i2c.o diff --git a/drivers/mfd/cgbc-core.c b/drivers/mfd/cgbc-core.c new file mode 100644 index 000000000000..93004a6b29c1 --- /dev/null +++ b/drivers/mfd/cgbc-core.c @@ -0,0 +1,411 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Congatec Board Controller core driver. + * + * The x86 Congatec modules have an embedded micro controller named Board + * Controller. This Board Controller has a Watchdog timer, some GPIOs, and two + * I2C busses. + * + * Copyright (C) 2024 Bootlin + * + * Author: Thomas Richard <thomas.richard@bootlin.com> + */ + +#include <linux/dmi.h> +#include <linux/iopoll.h> +#include <linux/mfd/cgbc.h> +#include <linux/mfd/core.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sysfs.h> + +#define CGBC_IO_SESSION_BASE 0x0E20 +#define CGBC_IO_SESSION_END 0x0E30 +#define CGBC_IO_CMD_BASE 0x0E00 +#define CGBC_IO_CMD_END 0x0E10 + +#define CGBC_MASK_STATUS (BIT(6) | BIT(7)) +#define CGBC_MASK_DATA_COUNT 0x1F +#define CGBC_MASK_ERROR_CODE 0x1F + +#define CGBC_STATUS_DATA_READY 0x00 +#define CGBC_STATUS_CMD_READY BIT(6) +#define CGBC_STATUS_ERROR (BIT(6) | BIT(7)) + +#define CGBC_SESSION_CMD 0x00 +#define CGBC_SESSION_CMD_IDLE 0x00 +#define CGBC_SESSION_CMD_REQUEST 0x01 +#define CGBC_SESSION_DATA 0x01 +#define CGBC_SESSION_STATUS 0x02 +#define CGBC_SESSION_STATUS_FREE 0x03 +#define CGBC_SESSION_ACCESS 0x04 +#define CGBC_SESSION_ACCESS_GAINED 0x00 + +#define CGBC_SESSION_VALID_MIN 0x02 +#define CGBC_SESSION_VALID_MAX 0xFE + +#define CGBC_CMD_STROBE 0x00 +#define CGBC_CMD_INDEX 0x02 +#define CGBC_CMD_INDEX_CBM_MAN8 0x00 +#define CGBC_CMD_INDEX_CBM_AUTO32 0x03 +#define CGBC_CMD_DATA 0x04 +#define CGBC_CMD_ACCESS 0x0C + +#define CGBC_CMD_GET_FW_REV 0x21 + +static struct platform_device *cgbc_pdev; + +/* Wait the Board Controller is ready to receive some session commands */ +static int cgbc_wait_device(struct cgbc_device_data *cgbc) +{ + u16 status; + int ret; + + ret = readx_poll_timeout(ioread16, cgbc->io_session + CGBC_SESSION_STATUS, status, + status == CGBC_SESSION_STATUS_FREE, 0, 500000); + + if (ret || ioread32(cgbc->io_session + CGBC_SESSION_ACCESS)) + ret = -ENODEV; + + return ret; +} + +static int cgbc_session_command(struct cgbc_device_data *cgbc, u8 cmd) +{ + int ret; + u8 val; + + ret = readx_poll_timeout(ioread8, cgbc->io_session + CGBC_SESSION_CMD, val, + val == CGBC_SESSION_CMD_IDLE, 0, 100000); + if (ret) + return ret; + + iowrite8(cmd, cgbc->io_session + CGBC_SESSION_CMD); + + ret = readx_poll_timeout(ioread8, cgbc->io_session + CGBC_SESSION_CMD, val, + val == CGBC_SESSION_CMD_IDLE, 0, 100000); + if (ret) + return ret; + + ret = (int)ioread8(cgbc->io_session + CGBC_SESSION_DATA); + + iowrite8(CGBC_SESSION_STATUS_FREE, cgbc->io_session + CGBC_SESSION_STATUS); + + return ret; +} + +static int cgbc_session_request(struct cgbc_device_data *cgbc) +{ + unsigned int ret; + + ret = cgbc_wait_device(cgbc); + + if (ret) + return dev_err_probe(cgbc->dev, ret, "device not found or not ready\n"); + + cgbc->session = cgbc_session_command(cgbc, CGBC_SESSION_CMD_REQUEST); + + /* The Board Controller sent us a wrong session handle, we cannot communicate with it */ + if (cgbc->session < CGBC_SESSION_VALID_MIN || cgbc->session > CGBC_SESSION_VALID_MAX) + return dev_err_probe(cgbc->dev, -ECONNREFUSED, + "failed to get a valid session handle\n"); + + return 0; +} + +static void cgbc_session_release(struct cgbc_device_data *cgbc) +{ + if (cgbc_session_command(cgbc, cgbc->session) != cgbc->session) + dev_warn(cgbc->dev, "failed to release session\n"); +} + +static bool cgbc_command_lock(struct cgbc_device_data *cgbc) +{ + iowrite8(cgbc->session, cgbc->io_cmd + CGBC_CMD_ACCESS); + + return ioread8(cgbc->io_cmd + CGBC_CMD_ACCESS) == cgbc->session; +} + +static void cgbc_command_unlock(struct cgbc_device_data *cgbc) +{ + iowrite8(cgbc->session, cgbc->io_cmd + CGBC_CMD_ACCESS); +} + +int cgbc_command(struct cgbc_device_data *cgbc, void *cmd, unsigned int cmd_size, void *data, + unsigned int data_size, u8 *status) +{ + u8 checksum = 0, data_checksum = 0, istatus = 0, val; + u8 *_data = (u8 *)data; + u8 *_cmd = (u8 *)cmd; + int mode_change = -1; + bool lock; + int ret, i; + + mutex_lock(&cgbc->lock); + + /* Request access */ + ret = readx_poll_timeout(cgbc_command_lock, cgbc, lock, lock, 0, 100000); + if (ret) + goto out; + + /* Wait board controller is ready */ + ret = readx_poll_timeout(ioread8, cgbc->io_cmd + CGBC_CMD_STROBE, val, + val == CGBC_CMD_STROBE, 0, 100000); + if (ret) + goto release; + + /* Write command packet */ + if (cmd_size <= 2) { + iowrite8(CGBC_CMD_INDEX_CBM_MAN8, cgbc->io_cmd + CGBC_CMD_INDEX); + } else { + iowrite8(CGBC_CMD_INDEX_CBM_AUTO32, cgbc->io_cmd + CGBC_CMD_INDEX); + if ((cmd_size % 4) != 0x03) + mode_change = (cmd_size & 0xFFFC) - 1; + } + + for (i = 0; i < cmd_size; i++) { + iowrite8(_cmd[i], cgbc->io_cmd + CGBC_CMD_DATA + (i % 4)); + checksum ^= _cmd[i]; + if (mode_change == i) + iowrite8((i + 1) | CGBC_CMD_INDEX_CBM_MAN8, cgbc->io_cmd + CGBC_CMD_INDEX); + } + + /* Append checksum byte */ + iowrite8(checksum, cgbc->io_cmd + CGBC_CMD_DATA + (i % 4)); + + /* Perform command strobe */ + iowrite8(cgbc->session, cgbc->io_cmd + CGBC_CMD_STROBE); + + /* Rewind cmd buffer index */ + iowrite8(CGBC_CMD_INDEX_CBM_AUTO32, cgbc->io_cmd + CGBC_CMD_INDEX); + + /* Wait command completion */ + ret = read_poll_timeout(ioread8, val, val == CGBC_CMD_STROBE, 0, 100000, false, + cgbc->io_cmd + CGBC_CMD_STROBE); + if (ret) + goto release; + + istatus = ioread8(cgbc->io_cmd + CGBC_CMD_DATA); + checksum = istatus; + + /* Check command status */ + switch (istatus & CGBC_MASK_STATUS) { + case CGBC_STATUS_DATA_READY: + if (istatus > data_size) + istatus = data_size; + for (i = 0; i < istatus; i++) { + _data[i] = ioread8(cgbc->io_cmd + CGBC_CMD_DATA + ((i + 1) % 4)); + checksum ^= _data[i]; + } + data_checksum = ioread8(cgbc->io_cmd + CGBC_CMD_DATA + ((i + 1) % 4)); + istatus &= CGBC_MASK_DATA_COUNT; + break; + case CGBC_STATUS_ERROR: + case CGBC_STATUS_CMD_READY: + data_checksum = ioread8(cgbc->io_cmd + CGBC_CMD_DATA + 1); + if ((istatus & CGBC_MASK_STATUS) == CGBC_STATUS_ERROR) + ret = -EIO; + istatus = istatus & CGBC_MASK_ERROR_CODE; + break; + default: + data_checksum = ioread8(cgbc->io_cmd + CGBC_CMD_DATA + 1); + istatus &= CGBC_MASK_ERROR_CODE; + ret = -EIO; + break; + } + + /* Checksum verification */ + if (ret == 0 && data_checksum != checksum) + ret = -EIO; + +release: + cgbc_command_unlock(cgbc); + +out: + mutex_unlock(&cgbc->lock); + + if (status) + *status = istatus; + + return ret; +} +EXPORT_SYMBOL_GPL(cgbc_command); + +static struct mfd_cell cgbc_devs[] = { + { .name = "cgbc-wdt" }, + { .name = "cgbc-gpio" }, + { .name = "cgbc-i2c", .id = 1 }, + { .name = "cgbc-i2c", .id = 2 }, +}; + +static int cgbc_map(struct cgbc_device_data *cgbc) +{ + struct device *dev = cgbc->dev; + struct platform_device *pdev = to_platform_device(dev); + struct resource *ioport; + + ioport = platform_get_resource(pdev, IORESOURCE_IO, 0); + if (!ioport) + return -EINVAL; + + cgbc->io_session = devm_ioport_map(dev, ioport->start, resource_size(ioport)); + if (!cgbc->io_session) + return -ENOMEM; + + ioport = platform_get_resource(pdev, IORESOURCE_IO, 1); + if (!ioport) + return -EINVAL; + + cgbc->io_cmd = devm_ioport_map(dev, ioport->start, resource_size(ioport)); + if (!cgbc->io_cmd) + return -ENOMEM; + + return 0; +} + +static const struct resource cgbc_resources[] = { + { + .start = CGBC_IO_SESSION_BASE, + .end = CGBC_IO_SESSION_END, + .flags = IORESOURCE_IO, + }, + { + .start = CGBC_IO_CMD_BASE, + .end = CGBC_IO_CMD_END, + .flags = IORESOURCE_IO, + }, +}; + +static ssize_t cgbc_version_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cgbc_device_data *cgbc = dev_get_drvdata(dev); + + return sysfs_emit(buf, "CGBCP%c%c%c\n", cgbc->version.feature, cgbc->version.major, + cgbc->version.minor); +} + +static DEVICE_ATTR_RO(cgbc_version); + +static struct attribute *cgbc_attrs[] = { + &dev_attr_cgbc_version.attr, + NULL +}; + +ATTRIBUTE_GROUPS(cgbc); + +static int cgbc_get_version(struct cgbc_device_data *cgbc) +{ + u8 cmd = CGBC_CMD_GET_FW_REV; + u8 data[4]; + int ret; + + ret = cgbc_command(cgbc, &cmd, 1, &data, sizeof(data), NULL); + if (ret) + return ret; + + cgbc->version.feature = data[0]; + cgbc->version.major = data[1]; + cgbc->version.minor = data[2]; + + return 0; +} + +static int cgbc_init_device(struct cgbc_device_data *cgbc) +{ + int ret; + + ret = cgbc_session_request(cgbc); + if (ret) + return ret; + + ret = cgbc_get_version(cgbc); + if (ret) + return ret; + + return mfd_add_devices(cgbc->dev, -1, cgbc_devs, ARRAY_SIZE(cgbc_devs), NULL, 0, NULL); +} + +static int cgbc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct cgbc_device_data *cgbc; + int ret; + + cgbc = devm_kzalloc(dev, sizeof(*cgbc), GFP_KERNEL); + if (!cgbc) + return -ENOMEM; + + cgbc->dev = dev; + + ret = cgbc_map(cgbc); + if (ret) + return ret; + + mutex_init(&cgbc->lock); + + platform_set_drvdata(pdev, cgbc); + + return cgbc_init_device(cgbc); +} + +static void cgbc_remove(struct platform_device *pdev) +{ + struct cgbc_device_data *cgbc = platform_get_drvdata(pdev); + + cgbc_session_release(cgbc); + + mfd_remove_devices(&pdev->dev); +} + +static struct platform_driver cgbc_driver = { + .driver = { + .name = "cgbc", + .dev_groups = cgbc_groups, + }, + .probe = cgbc_probe, + .remove_new = cgbc_remove, +}; + +static const struct dmi_system_id cgbc_dmi_table[] __initconst = { + { + .ident = "SA7", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "congatec"), + DMI_MATCH(DMI_BOARD_NAME, "conga-SA7"), + }, + }, + {} +}; +MODULE_DEVICE_TABLE(dmi, cgbc_dmi_table); + +static int __init cgbc_init(void) +{ + const struct dmi_system_id *id; + int ret = -ENODEV; + + id = dmi_first_match(cgbc_dmi_table); + if (IS_ERR_OR_NULL(id)) + return ret; + + cgbc_pdev = platform_device_register_simple("cgbc", PLATFORM_DEVID_NONE, cgbc_resources, + ARRAY_SIZE(cgbc_resources)); + if (IS_ERR(cgbc_pdev)) + return PTR_ERR(cgbc_pdev); + + return platform_driver_register(&cgbc_driver); +} + +static void __exit cgbc_exit(void) +{ + platform_device_unregister(cgbc_pdev); + platform_driver_unregister(&cgbc_driver); +} + +module_init(cgbc_init); +module_exit(cgbc_exit); + +MODULE_DESCRIPTION("Congatec Board Controller Core Driver"); +MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:cgbc-core"); diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 684b9fe84fff..755cf3559540 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1151,6 +1151,16 @@ config ALIM7101_WDT Most people will say N. +config CGBC_WDT + tristate "Congatec Board Controller Watchdog Timer" + depends on MFD_CGBC + select WATCHDOG_CORE + help + Enables watchdog timer support for the Congatec Board Controller. + + This driver can also be built as a module. If so, the module will be + called cgbc_wdt. + config EBC_C384_WDT tristate "WinSystems EBC-C384 Watchdog Timer" depends on (X86 || COMPILE_TEST) && HAS_IOPORT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index ab6f2b41e38e..386d88d89fe5 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -107,6 +107,7 @@ obj-$(CONFIG_ADVANTECH_WDT) += advantechwdt.o obj-$(CONFIG_ADVANTECH_EC_WDT) += advantech_ec_wdt.o obj-$(CONFIG_ALIM1535_WDT) += alim1535_wdt.o obj-$(CONFIG_ALIM7101_WDT) += alim7101_wdt.o +obj-$(CONFIG_CGBC_WDT) += cgbc_wdt.o obj-$(CONFIG_EBC_C384_WDT) += ebc-c384_wdt.o obj-$(CONFIG_EXAR_WDT) += exar_wdt.o obj-$(CONFIG_F71808E_WDT) += f71808e_wdt.o diff --git a/drivers/watchdog/cgbc_wdt.c b/drivers/watchdog/cgbc_wdt.c new file mode 100644 index 000000000000..702b055ba6f4 --- /dev/null +++ b/drivers/watchdog/cgbc_wdt.c @@ -0,0 +1,211 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Congatec Board Controller watchdog driver + * + * Copyright (C) 2024 Bootlin + * Author: Thomas Richard <thomas.richard@bootlin.com> + */ + +#include <linux/build_bug.h> +#include <linux/device.h> +#include <linux/limits.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> + +#include <linux/mfd/cgbc.h> + +#define CGBC_WDT_CMD_TRIGGER 0x27 +#define CGBC_WDT_CMD_INIT 0x28 +#define CGBC_WDT_DISABLE 0x00 + +#define CGBC_WDT_MODE_SINGLE_EVENT 0x02 + +#define CGBC_WDT_MIN_TIMEOUT 1 +#define CGBC_WDT_MAX_TIMEOUT ((U32_MAX >> 8) / 1000) + +#define CGBC_WDT_DEFAULT_TIMEOUT 30 +#define CGBC_WDT_DEFAULT_PRETIMEOUT 0 + +enum action { + ACTION_INT = 0, + ACTION_SMI, + ACTION_RESET, + ACTION_BUTTON, +}; + +static unsigned int timeout; +module_param(timeout, uint, 0); +MODULE_PARM_DESC(timeout, + "Watchdog timeout in seconds. (>=0, default=" + __MODULE_STRING(CGBC_WDT_DEFAULT_TIMEOUT) ")"); + +static unsigned int pretimeout = CGBC_WDT_DEFAULT_PRETIMEOUT; +module_param(pretimeout, uint, 0); +MODULE_PARM_DESC(pretimeout, + "Watchdog pretimeout in seconds. (>=0, default=" + __MODULE_STRING(CGBC_WDT_DEFAULT_PRETIMEOUT) ")"); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, + "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +struct cgbc_wdt_data { + struct cgbc_device_data *cgbc; + struct watchdog_device wdd; +}; + +struct cgbc_wdt_cmd_cfg { + u8 cmd; + u8 mode; + u8 action; + u8 timeout1[3]; + u8 timeout2[3]; + u8 reserved[3]; + u8 delay[3]; +} __packed; + +static_assert(sizeof(struct cgbc_wdt_cmd_cfg) == 15); + +static int cgbc_wdt_start(struct watchdog_device *wdd) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + struct cgbc_device_data *cgbc = wdt_data->cgbc; + unsigned int timeout1 = (wdd->timeout - wdd->pretimeout) * 1000; + unsigned int timeout2 = wdd->pretimeout * 1000; + u8 action; + + struct cgbc_wdt_cmd_cfg cmd_start = { + .cmd = CGBC_WDT_CMD_INIT, + .mode = CGBC_WDT_MODE_SINGLE_EVENT, + .timeout1[0] = (u8)timeout1, + .timeout1[1] = (u8)(timeout1 >> 8), + .timeout1[2] = (u8)(timeout1 >> 16), + .timeout2[0] = (u8)timeout2, + .timeout2[1] = (u8)(timeout2 >> 8), + .timeout2[2] = (u8)(timeout2 >> 16), + }; + + if (wdd->pretimeout) { + action = 2; + action |= ACTION_SMI << 2; + action |= ACTION_RESET << 4; + } else { + action = 1; + action |= ACTION_RESET << 2; + } + + cmd_start.action = action; + + return cgbc_command(cgbc, &cmd_start, sizeof(cmd_start), NULL, 0, NULL); +} + +static int cgbc_wdt_stop(struct watchdog_device *wdd) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + struct cgbc_device_data *cgbc = wdt_data->cgbc; + struct cgbc_wdt_cmd_cfg cmd_stop = { + .cmd = CGBC_WDT_CMD_INIT, + .mode = CGBC_WDT_DISABLE, + }; + + return cgbc_command(cgbc, &cmd_stop, sizeof(cmd_stop), NULL, 0, NULL); +} + +static int cgbc_wdt_keepalive(struct watchdog_device *wdd) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + struct cgbc_device_data *cgbc = wdt_data->cgbc; + u8 cmd_ping = CGBC_WDT_CMD_TRIGGER; + + return cgbc_command(cgbc, &cmd_ping, sizeof(cmd_ping), NULL, 0, NULL); +} + +static int cgbc_wdt_set_pretimeout(struct watchdog_device *wdd, + unsigned int pretimeout) +{ + wdd->pretimeout = pretimeout; + + if (watchdog_active(wdd)) + return cgbc_wdt_start(wdd); + + return 0; +} + +static int cgbc_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + if (timeout < wdd->pretimeout) + wdd->pretimeout = 0; + + wdd->timeout = timeout; + + if (watchdog_active(wdd)) + return cgbc_wdt_start(wdd); + + return 0; +} + +static const struct watchdog_info cgbc_wdt_info = { + .identity = "CGBC Watchdog", + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT +}; + +static const struct watchdog_ops cgbc_wdt_ops = { + .owner = THIS_MODULE, + .start = cgbc_wdt_start, + .stop = cgbc_wdt_stop, + .ping = cgbc_wdt_keepalive, + .set_timeout = cgbc_wdt_set_timeout, + .set_pretimeout = cgbc_wdt_set_pretimeout, +}; + +static int cgbc_wdt_probe(struct platform_device *pdev) +{ + struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct cgbc_wdt_data *wdt_data; + struct watchdog_device *wdd; + + wdt_data = devm_kzalloc(dev, sizeof(*wdt_data), GFP_KERNEL); + if (!wdt_data) + return -ENOMEM; + + wdt_data->cgbc = cgbc; + wdd = &wdt_data->wdd; + wdd->parent = dev; + + wdd->info = &cgbc_wdt_info; + wdd->ops = &cgbc_wdt_ops; + wdd->max_timeout = CGBC_WDT_MAX_TIMEOUT; + wdd->min_timeout = CGBC_WDT_MIN_TIMEOUT; + + watchdog_set_drvdata(wdd, wdt_data); + watchdog_set_nowayout(wdd, nowayout); + + wdd->timeout = CGBC_WDT_DEFAULT_TIMEOUT; + watchdog_init_timeout(wdd, timeout, dev); + cgbc_wdt_set_pretimeout(wdd, pretimeout); + + platform_set_drvdata(pdev, wdt_data); + watchdog_stop_on_reboot(wdd); + watchdog_stop_on_unregister(wdd); + + return devm_watchdog_register_device(dev, wdd); +} + +static struct platform_driver cgbc_wdt_driver = { + .driver = { + .name = "cgbc-wdt", + }, + .probe = cgbc_wdt_probe, +}; + +module_platform_driver(cgbc_wdt_driver); + +MODULE_DESCRIPTION("Congatec Board Controller Watchdog Driver"); +MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/mfd/cgbc.h b/include/linux/mfd/cgbc.h new file mode 100644 index 000000000000..badbec4c7033 --- /dev/null +++ b/include/linux/mfd/cgbc.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Congatec Board Controller driver definitions + * + * Copyright (C) 2024 Bootlin + * Author: Thomas Richard <thomas.richard@bootlin.com> + */ + +#ifndef _LINUX_MFD_CGBC_H_ + +/** + * struct cgbc_version - Board Controller device version structure + * @feature: Board Controller feature number + * @major: Board Controller major revision + * @minor: Board Controller minor revision + */ +struct cgbc_version { + unsigned char feature; + unsigned char major; + unsigned char minor; +}; + +/** + * struct cgbc_device_data - Internal representation of the Board Controller device + * @io_session: Pointer to the session IO memory + * @io_cmd: Pointer to the command IO memory + * @session: Session id returned by the Board Controller + * @dev: Pointer to kernel device structure + * @cgbc_version: Board Controller version structure + * @mutex: Board Controller mutex + */ +struct cgbc_device_data { + void __iomem *io_session; + void __iomem *io_cmd; + u8 session; + struct device *dev; + struct cgbc_version version; + struct mutex lock; +}; + +int cgbc_command(struct cgbc_device_data *cgbc, void *cmd, unsigned int cmd_size, + void *data, unsigned int data_size, u8 *status); + +#endif /*_LINUX_MFD_CGBC_H_*/ |