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path: root/drivers/platform/x86/barco-p50-gpio.c
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Diffstat (limited to 'drivers/platform/x86/barco-p50-gpio.c')
-rw-r--r--drivers/platform/x86/barco-p50-gpio.c436
1 files changed, 436 insertions, 0 deletions
diff --git a/drivers/platform/x86/barco-p50-gpio.c b/drivers/platform/x86/barco-p50-gpio.c
new file mode 100644
index 0000000000..af566f7120
--- /dev/null
+++ b/drivers/platform/x86/barco-p50-gpio.c
@@ -0,0 +1,436 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * Support for EC-connected GPIOs for identify
+ * LED/button on Barco P50 board
+ *
+ * Copyright (C) 2021 Barco NV
+ * Author: Santosh Kumar Yadav <santoshkumar.yadav@barco.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/delay.h>
+#include <linux/dmi.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/gpio_keys.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/machine.h>
+#include <linux/input.h>
+
+
+#define DRIVER_NAME "barco-p50-gpio"
+
+/* GPIO lines */
+#define P50_GPIO_LINE_LED 0
+#define P50_GPIO_LINE_BTN 1
+
+/* GPIO IO Ports */
+#define P50_GPIO_IO_PORT_BASE 0x299
+
+#define P50_PORT_DATA 0x00
+#define P50_PORT_CMD 0x01
+
+#define P50_STATUS_OBF 0x01 /* EC output buffer full */
+#define P50_STATUS_IBF 0x02 /* EC input buffer full */
+
+#define P50_CMD_READ 0xa0
+#define P50_CMD_WRITE 0x50
+
+/* EC mailbox registers */
+#define P50_MBOX_REG_CMD 0x00
+#define P50_MBOX_REG_STATUS 0x01
+#define P50_MBOX_REG_PARAM 0x02
+#define P50_MBOX_REG_DATA 0x03
+
+#define P50_MBOX_CMD_READ_GPIO 0x11
+#define P50_MBOX_CMD_WRITE_GPIO 0x12
+#define P50_MBOX_CMD_CLEAR 0xff
+
+#define P50_MBOX_STATUS_SUCCESS 0x01
+
+#define P50_MBOX_PARAM_LED 0x12
+#define P50_MBOX_PARAM_BTN 0x13
+
+
+struct p50_gpio {
+ struct gpio_chip gc;
+ struct mutex lock;
+ unsigned long base;
+ struct platform_device *leds_pdev;
+ struct platform_device *keys_pdev;
+};
+
+static struct platform_device *gpio_pdev;
+
+static int gpio_params[] = {
+ [P50_GPIO_LINE_LED] = P50_MBOX_PARAM_LED,
+ [P50_GPIO_LINE_BTN] = P50_MBOX_PARAM_BTN,
+};
+
+static const char * const gpio_names[] = {
+ [P50_GPIO_LINE_LED] = "identify-led",
+ [P50_GPIO_LINE_BTN] = "identify-button",
+};
+
+
+static struct gpiod_lookup_table p50_gpio_led_table = {
+ .dev_id = "leds-gpio",
+ .table = {
+ GPIO_LOOKUP_IDX(DRIVER_NAME, P50_GPIO_LINE_LED, NULL, 0, GPIO_ACTIVE_HIGH),
+ {}
+ }
+};
+
+/* GPIO LEDs */
+static struct gpio_led leds[] = {
+ { .name = "identify" }
+};
+
+static struct gpio_led_platform_data leds_pdata = {
+ .num_leds = ARRAY_SIZE(leds),
+ .leds = leds,
+};
+
+/* GPIO keyboard */
+static struct gpio_keys_button buttons[] = {
+ {
+ .code = KEY_VENDOR,
+ .gpio = P50_GPIO_LINE_BTN,
+ .active_low = 1,
+ .type = EV_KEY,
+ .value = 1,
+ },
+};
+
+static struct gpio_keys_platform_data keys_pdata = {
+ .buttons = buttons,
+ .nbuttons = ARRAY_SIZE(buttons),
+ .poll_interval = 100,
+ .rep = 0,
+ .name = "identify",
+};
+
+
+/* low level access routines */
+
+static int p50_wait_ec(struct p50_gpio *p50, int mask, int expected)
+{
+ int i, val;
+
+ for (i = 0; i < 100; i++) {
+ val = inb(p50->base + P50_PORT_CMD) & mask;
+ if (val == expected)
+ return 0;
+ usleep_range(500, 2000);
+ }
+
+ dev_err(p50->gc.parent, "Timed out waiting for EC (0x%x)\n", val);
+ return -ETIMEDOUT;
+}
+
+
+static int p50_read_mbox_reg(struct p50_gpio *p50, int reg)
+{
+ int ret;
+
+ ret = p50_wait_ec(p50, P50_STATUS_IBF, 0);
+ if (ret)
+ return ret;
+
+ /* clear output buffer flag, prevent unfinished commands */
+ inb(p50->base + P50_PORT_DATA);
+
+ /* cmd/address */
+ outb(P50_CMD_READ | reg, p50->base + P50_PORT_CMD);
+
+ ret = p50_wait_ec(p50, P50_STATUS_OBF, P50_STATUS_OBF);
+ if (ret)
+ return ret;
+
+ return inb(p50->base + P50_PORT_DATA);
+}
+
+static int p50_write_mbox_reg(struct p50_gpio *p50, int reg, int val)
+{
+ int ret;
+
+ ret = p50_wait_ec(p50, P50_STATUS_IBF, 0);
+ if (ret)
+ return ret;
+
+ /* cmd/address */
+ outb(P50_CMD_WRITE | reg, p50->base + P50_PORT_CMD);
+
+ ret = p50_wait_ec(p50, P50_STATUS_IBF, 0);
+ if (ret)
+ return ret;
+
+ /* data */
+ outb(val, p50->base + P50_PORT_DATA);
+
+ return 0;
+}
+
+
+/* mbox routines */
+
+static int p50_wait_mbox_idle(struct p50_gpio *p50)
+{
+ int i, val;
+
+ for (i = 0; i < 1000; i++) {
+ val = p50_read_mbox_reg(p50, P50_MBOX_REG_CMD);
+ /* cmd is 0 when idle */
+ if (val <= 0)
+ return val;
+
+ usleep_range(500, 2000);
+ }
+
+ dev_err(p50->gc.parent, "Timed out waiting for EC mbox idle (CMD: 0x%x)\n", val);
+
+ return -ETIMEDOUT;
+}
+
+static int p50_send_mbox_cmd(struct p50_gpio *p50, int cmd, int param, int data)
+{
+ int ret;
+
+ ret = p50_wait_mbox_idle(p50);
+ if (ret)
+ return ret;
+
+ ret = p50_write_mbox_reg(p50, P50_MBOX_REG_DATA, data);
+ if (ret)
+ return ret;
+
+ ret = p50_write_mbox_reg(p50, P50_MBOX_REG_PARAM, param);
+ if (ret)
+ return ret;
+
+ ret = p50_write_mbox_reg(p50, P50_MBOX_REG_CMD, cmd);
+ if (ret)
+ return ret;
+
+ ret = p50_wait_mbox_idle(p50);
+ if (ret)
+ return ret;
+
+ ret = p50_read_mbox_reg(p50, P50_MBOX_REG_STATUS);
+ if (ret < 0)
+ return ret;
+
+ if (ret == P50_MBOX_STATUS_SUCCESS)
+ return 0;
+
+ dev_err(p50->gc.parent, "Mbox command failed (CMD=0x%x STAT=0x%x PARAM=0x%x DATA=0x%x)\n",
+ cmd, ret, param, data);
+
+ return -EIO;
+}
+
+
+/* gpio routines */
+
+static int p50_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ switch (offset) {
+ case P50_GPIO_LINE_BTN:
+ return GPIO_LINE_DIRECTION_IN;
+
+ case P50_GPIO_LINE_LED:
+ return GPIO_LINE_DIRECTION_OUT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int p50_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+ struct p50_gpio *p50 = gpiochip_get_data(gc);
+ int ret;
+
+ mutex_lock(&p50->lock);
+
+ ret = p50_send_mbox_cmd(p50, P50_MBOX_CMD_READ_GPIO, gpio_params[offset], 0);
+ if (ret == 0)
+ ret = p50_read_mbox_reg(p50, P50_MBOX_REG_DATA);
+
+ mutex_unlock(&p50->lock);
+
+ return ret;
+}
+
+static void p50_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
+{
+ struct p50_gpio *p50 = gpiochip_get_data(gc);
+
+ mutex_lock(&p50->lock);
+
+ p50_send_mbox_cmd(p50, P50_MBOX_CMD_WRITE_GPIO, gpio_params[offset], value);
+
+ mutex_unlock(&p50->lock);
+}
+
+static int p50_gpio_probe(struct platform_device *pdev)
+{
+ struct p50_gpio *p50;
+ struct resource *res;
+ int ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "Cannot get I/O ports\n");
+ return -ENODEV;
+ }
+
+ if (!devm_request_region(&pdev->dev, res->start, resource_size(res), pdev->name)) {
+ dev_err(&pdev->dev, "Unable to reserve I/O region\n");
+ return -EBUSY;
+ }
+
+ p50 = devm_kzalloc(&pdev->dev, sizeof(*p50), GFP_KERNEL);
+ if (!p50)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, p50);
+ mutex_init(&p50->lock);
+ p50->base = res->start;
+ p50->gc.owner = THIS_MODULE;
+ p50->gc.parent = &pdev->dev;
+ p50->gc.label = dev_name(&pdev->dev);
+ p50->gc.ngpio = ARRAY_SIZE(gpio_names);
+ p50->gc.names = gpio_names;
+ p50->gc.can_sleep = true;
+ p50->gc.base = -1;
+ p50->gc.get_direction = p50_gpio_get_direction;
+ p50->gc.get = p50_gpio_get;
+ p50->gc.set = p50_gpio_set;
+
+
+ /* reset mbox */
+ ret = p50_wait_mbox_idle(p50);
+ if (ret)
+ return ret;
+
+ ret = p50_write_mbox_reg(p50, P50_MBOX_REG_CMD, P50_MBOX_CMD_CLEAR);
+ if (ret)
+ return ret;
+
+ ret = p50_wait_mbox_idle(p50);
+ if (ret)
+ return ret;
+
+
+ ret = devm_gpiochip_add_data(&pdev->dev, &p50->gc, p50);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register gpiochip: %d\n", ret);
+ return ret;
+ }
+
+ gpiod_add_lookup_table(&p50_gpio_led_table);
+
+ p50->leds_pdev = platform_device_register_data(&pdev->dev,
+ "leds-gpio", PLATFORM_DEVID_NONE, &leds_pdata, sizeof(leds_pdata));
+
+ if (IS_ERR(p50->leds_pdev)) {
+ ret = PTR_ERR(p50->leds_pdev);
+ dev_err(&pdev->dev, "Could not register leds-gpio: %d\n", ret);
+ goto err_leds;
+ }
+
+ /* gpio-keys-polled uses old-style gpio interface, pass the right identifier */
+ buttons[0].gpio += p50->gc.base;
+
+ p50->keys_pdev =
+ platform_device_register_data(&pdev->dev, "gpio-keys-polled",
+ PLATFORM_DEVID_NONE,
+ &keys_pdata, sizeof(keys_pdata));
+
+ if (IS_ERR(p50->keys_pdev)) {
+ ret = PTR_ERR(p50->keys_pdev);
+ dev_err(&pdev->dev, "Could not register gpio-keys-polled: %d\n", ret);
+ goto err_keys;
+ }
+
+ return 0;
+
+err_keys:
+ platform_device_unregister(p50->leds_pdev);
+err_leds:
+ gpiod_remove_lookup_table(&p50_gpio_led_table);
+
+ return ret;
+}
+
+static void p50_gpio_remove(struct platform_device *pdev)
+{
+ struct p50_gpio *p50 = platform_get_drvdata(pdev);
+
+ platform_device_unregister(p50->keys_pdev);
+ platform_device_unregister(p50->leds_pdev);
+
+ gpiod_remove_lookup_table(&p50_gpio_led_table);
+}
+
+static struct platform_driver p50_gpio_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ },
+ .probe = p50_gpio_probe,
+ .remove_new = p50_gpio_remove,
+};
+
+/* Board setup */
+static const struct dmi_system_id dmi_ids[] __initconst = {
+ {
+ .matches = {
+ DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Barco"),
+ DMI_EXACT_MATCH(DMI_PRODUCT_FAMILY, "P50")
+ },
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(dmi, dmi_ids);
+
+static int __init p50_module_init(void)
+{
+ struct resource res = DEFINE_RES_IO(P50_GPIO_IO_PORT_BASE, P50_PORT_CMD + 1);
+ int ret;
+
+ if (!dmi_first_match(dmi_ids))
+ return -ENODEV;
+
+ ret = platform_driver_register(&p50_gpio_driver);
+ if (ret)
+ return ret;
+
+ gpio_pdev = platform_device_register_simple(DRIVER_NAME, PLATFORM_DEVID_NONE, &res, 1);
+ if (IS_ERR(gpio_pdev)) {
+ pr_err("failed registering %s: %ld\n", DRIVER_NAME, PTR_ERR(gpio_pdev));
+ platform_driver_unregister(&p50_gpio_driver);
+ return PTR_ERR(gpio_pdev);
+ }
+
+ return 0;
+}
+
+static void __exit p50_module_exit(void)
+{
+ platform_device_unregister(gpio_pdev);
+ platform_driver_unregister(&p50_gpio_driver);
+}
+
+module_init(p50_module_init);
+module_exit(p50_module_exit);
+
+MODULE_AUTHOR("Santosh Kumar Yadav, Barco NV <santoshkumar.yadav@barco.com>");
+MODULE_DESCRIPTION("Barco P50 identify GPIOs driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 09:03:06 +0000