diff options
Diffstat (limited to 'drivers/input/touchscreen/himax_hx852x.c')
| -rw-r--r-- | drivers/input/touchscreen/himax_hx852x.c | 503 |
1 files changed, 503 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/himax_hx852x.c b/drivers/input/touchscreen/himax_hx852x.c new file mode 100644 index 000000000000..83c60e137a55 --- /dev/null +++ b/drivers/input/touchscreen/himax_hx852x.c @@ -0,0 +1,503 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Himax HX852x(ES) Touchscreen Driver + * Copyright (c) 2020-2024 Stephan Gerhold <stephan@gerhold.net> + * Copyright (c) 2020 Jonathan Albrieux <jonathan.albrieux@gmail.com> + * + * Based on the Himax Android Driver Sample Code Ver 0.3 for HMX852xES chipset: + * Copyright (c) 2014 Himax Corporation. + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/input/mt.h> +#include <linux/input/touchscreen.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/regulator/consumer.h> +#include <linux/unaligned.h> + +#define HX852X_COORD_SIZE(fingers) ((fingers) * sizeof(struct hx852x_coord)) +#define HX852X_WIDTH_SIZE(fingers) ALIGN(fingers, 4) +#define HX852X_BUF_SIZE(fingers) (HX852X_COORD_SIZE(fingers) + \ + HX852X_WIDTH_SIZE(fingers) + \ + sizeof(struct hx852x_touch_info)) + +#define HX852X_MAX_FINGERS 12 +#define HX852X_MAX_KEY_COUNT 4 +#define HX852X_MAX_BUF_SIZE HX852X_BUF_SIZE(HX852X_MAX_FINGERS) + +#define HX852X_TS_SLEEP_IN 0x80 +#define HX852X_TS_SLEEP_OUT 0x81 +#define HX852X_TS_SENSE_OFF 0x82 +#define HX852X_TS_SENSE_ON 0x83 +#define HX852X_READ_ONE_EVENT 0x85 +#define HX852X_READ_ALL_EVENTS 0x86 +#define HX852X_READ_LATEST_EVENT 0x87 +#define HX852X_CLEAR_EVENT_STACK 0x88 + +#define HX852X_REG_SRAM_SWITCH 0x8c +#define HX852X_REG_SRAM_ADDR 0x8b +#define HX852X_REG_FLASH_RPLACE 0x5a + +#define HX852X_SRAM_SWITCH_TEST_MODE 0x14 +#define HX852X_SRAM_ADDR_CONFIG 0x7000 + +struct hx852x { + struct i2c_client *client; + struct input_dev *input_dev; + struct touchscreen_properties props; + struct gpio_desc *reset_gpiod; + struct regulator_bulk_data supplies[2]; + unsigned int max_fingers; + unsigned int keycount; + unsigned int keycodes[HX852X_MAX_KEY_COUNT]; +}; + +struct hx852x_config { + u8 rx_num; + u8 tx_num; + u8 max_pt; + u8 padding1[3]; + __be16 x_res; + __be16 y_res; + u8 padding2[2]; +} __packed __aligned(4); + +struct hx852x_coord { + __be16 x; + __be16 y; +} __packed __aligned(4); + +struct hx852x_touch_info { + u8 finger_num; + __le16 finger_pressed; + u8 padding; +} __packed __aligned(4); + +static int hx852x_i2c_read(struct hx852x *hx, u8 cmd, void *data, u16 len) +{ + struct i2c_client *client = hx->client; + int error; + int ret; + + struct i2c_msg msg[] = { + { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &cmd, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = len, + .buf = data, + }, + }; + + ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + if (ret != ARRAY_SIZE(msg)) { + error = ret < 0 ? ret : -EIO; + dev_err(&client->dev, "failed to read %#x: %d\n", cmd, error); + return error; + } + + return 0; +} + +static int hx852x_power_on(struct hx852x *hx) +{ + struct device *dev = &hx->client->dev; + int error; + + error = regulator_bulk_enable(ARRAY_SIZE(hx->supplies), hx->supplies); + if (error) { + dev_err(dev, "failed to enable regulators: %d\n", error); + return error; + } + + gpiod_set_value_cansleep(hx->reset_gpiod, 1); + msleep(20); + gpiod_set_value_cansleep(hx->reset_gpiod, 0); + msleep(50); + + return 0; +} + +static int hx852x_start(struct hx852x *hx) +{ + struct device *dev = &hx->client->dev; + int error; + + error = i2c_smbus_write_byte(hx->client, HX852X_TS_SLEEP_OUT); + if (error) { + dev_err(dev, "failed to send TS_SLEEP_OUT: %d\n", error); + return error; + } + msleep(30); + + error = i2c_smbus_write_byte(hx->client, HX852X_TS_SENSE_ON); + if (error) { + dev_err(dev, "failed to send TS_SENSE_ON: %d\n", error); + return error; + } + msleep(20); + + return 0; +} + +static int hx852x_stop(struct hx852x *hx) +{ + struct device *dev = &hx->client->dev; + int error; + + error = i2c_smbus_write_byte(hx->client, HX852X_TS_SENSE_OFF); + if (error) { + dev_err(dev, "failed to send TS_SENSE_OFF: %d\n", error); + return error; + } + msleep(20); + + error = i2c_smbus_write_byte(hx->client, HX852X_TS_SLEEP_IN); + if (error) { + dev_err(dev, "failed to send TS_SLEEP_IN: %d\n", error); + return error; + } + msleep(30); + + return 0; +} + +static int hx852x_power_off(struct hx852x *hx) +{ + struct device *dev = &hx->client->dev; + int error; + + error = regulator_bulk_disable(ARRAY_SIZE(hx->supplies), hx->supplies); + if (error) { + dev_err(dev, "failed to disable regulators: %d\n", error); + return error; + } + + return 0; +} + +static int hx852x_read_config(struct hx852x *hx) +{ + struct device *dev = &hx->client->dev; + struct hx852x_config conf; + int x_res, y_res; + int error, error2; + + error = hx852x_power_on(hx); + if (error) + return error; + + /* Sensing must be turned on briefly to load the config */ + error = hx852x_start(hx); + if (error) + goto err_power_off; + + error = hx852x_stop(hx); + if (error) + goto err_power_off; + + error = i2c_smbus_write_byte_data(hx->client, HX852X_REG_SRAM_SWITCH, + HX852X_SRAM_SWITCH_TEST_MODE); + if (error) + goto err_power_off; + + error = i2c_smbus_write_word_data(hx->client, HX852X_REG_SRAM_ADDR, + HX852X_SRAM_ADDR_CONFIG); + if (error) + goto err_test_mode; + + error = hx852x_i2c_read(hx, HX852X_REG_FLASH_RPLACE, &conf, sizeof(conf)); + if (error) + goto err_test_mode; + + x_res = be16_to_cpu(conf.x_res); + y_res = be16_to_cpu(conf.y_res); + hx->max_fingers = (conf.max_pt & 0xf0) >> 4; + dev_dbg(dev, "x res: %u, y res: %u, max fingers: %u\n", + x_res, y_res, hx->max_fingers); + + if (hx->max_fingers > HX852X_MAX_FINGERS) { + dev_err(dev, "max supported fingers: %u, found: %u\n", + HX852X_MAX_FINGERS, hx->max_fingers); + error = -EINVAL; + goto err_test_mode; + } + + if (x_res && y_res) { + input_set_abs_params(hx->input_dev, ABS_MT_POSITION_X, 0, x_res - 1, 0, 0); + input_set_abs_params(hx->input_dev, ABS_MT_POSITION_Y, 0, y_res - 1, 0, 0); + } + +err_test_mode: + error2 = i2c_smbus_write_byte_data(hx->client, HX852X_REG_SRAM_SWITCH, 0); + error = error ?: error2; +err_power_off: + error2 = hx852x_power_off(hx); + return error ?: error2; +} + +static int hx852x_handle_events(struct hx852x *hx) +{ + /* + * The event packets have variable size, depending on the amount of + * supported fingers (hx->max_fingers). They are laid out as follows: + * - struct hx852x_coord[hx->max_fingers]: Coordinates for each finger + * - u8[ALIGN(hx->max_fingers, 4)]: Touch width for each finger + * with padding for 32-bit alignment + * - struct hx852x_touch_info + * + * Load everything into a 32-bit aligned buffer so the coordinates + * can be assigned directly, without using get_unaligned_*(). + */ + u8 buf[HX852X_MAX_BUF_SIZE] __aligned(4); + struct hx852x_coord *coord = (struct hx852x_coord *)buf; + u8 *width = &buf[HX852X_COORD_SIZE(hx->max_fingers)]; + struct hx852x_touch_info *info = (struct hx852x_touch_info *) + &width[HX852X_WIDTH_SIZE(hx->max_fingers)]; + unsigned long finger_pressed, key_pressed; + unsigned int i, x, y, w; + int error; + + error = hx852x_i2c_read(hx, HX852X_READ_ALL_EVENTS, buf, + HX852X_BUF_SIZE(hx->max_fingers)); + if (error) + return error; + + finger_pressed = get_unaligned_le16(&info->finger_pressed); + key_pressed = finger_pressed >> HX852X_MAX_FINGERS; + + /* All bits are set when no touch is detected */ + if (info->finger_num == 0xff || !(info->finger_num & 0x0f)) + finger_pressed = 0; + if (key_pressed == 0xf) + key_pressed = 0; + + for_each_set_bit(i, &finger_pressed, hx->max_fingers) { + x = be16_to_cpu(coord[i].x); + y = be16_to_cpu(coord[i].y); + w = width[i]; + + input_mt_slot(hx->input_dev, i); + input_mt_report_slot_state(hx->input_dev, MT_TOOL_FINGER, 1); + touchscreen_report_pos(hx->input_dev, &hx->props, x, y, true); + input_report_abs(hx->input_dev, ABS_MT_TOUCH_MAJOR, w); + } + input_mt_sync_frame(hx->input_dev); + + for (i = 0; i < hx->keycount; i++) + input_report_key(hx->input_dev, hx->keycodes[i], key_pressed & BIT(i)); + + input_sync(hx->input_dev); + return 0; +} + +static irqreturn_t hx852x_interrupt(int irq, void *ptr) +{ + struct hx852x *hx = ptr; + int error; + + error = hx852x_handle_events(hx); + if (error) { + dev_err_ratelimited(&hx->client->dev, + "failed to handle events: %d\n", error); + return IRQ_NONE; + } + + return IRQ_HANDLED; +} + +static int hx852x_input_open(struct input_dev *dev) +{ + struct hx852x *hx = input_get_drvdata(dev); + int error; + + error = hx852x_power_on(hx); + if (error) + return error; + + error = hx852x_start(hx); + if (error) { + hx852x_power_off(hx); + return error; + } + + enable_irq(hx->client->irq); + return 0; +} + +static void hx852x_input_close(struct input_dev *dev) +{ + struct hx852x *hx = input_get_drvdata(dev); + + hx852x_stop(hx); + disable_irq(hx->client->irq); + hx852x_power_off(hx); +} + +static int hx852x_parse_properties(struct hx852x *hx) +{ + struct device *dev = &hx->client->dev; + int error, count; + + count = device_property_count_u32(dev, "linux,keycodes"); + if (count == -EINVAL) { + /* Property does not exist, keycodes are optional */ + return 0; + } else if (count < 0) { + dev_err(dev, "Failed to read linux,keycodes: %d\n", count); + return count; + } else if (count > HX852X_MAX_KEY_COUNT) { + dev_err(dev, "max supported keys: %u, found: %u\n", + HX852X_MAX_KEY_COUNT, hx->keycount); + return -EINVAL; + } + hx->keycount = count; + + error = device_property_read_u32_array(dev, "linux,keycodes", + hx->keycodes, hx->keycount); + if (error) { + dev_err(dev, "failed to read linux,keycodes: %d\n", error); + return error; + } + + return 0; +} + +static int hx852x_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct hx852x *hx; + int error, i; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | + I2C_FUNC_SMBUS_WRITE_BYTE | + I2C_FUNC_SMBUS_WRITE_BYTE_DATA | + I2C_FUNC_SMBUS_WRITE_WORD_DATA)) { + dev_err(dev, "not all required i2c functionality supported\n"); + return -ENXIO; + } + + hx = devm_kzalloc(dev, sizeof(*hx), GFP_KERNEL); + if (!hx) + return -ENOMEM; + + hx->client = client; + hx->input_dev = devm_input_allocate_device(dev); + if (!hx->input_dev) + return -ENOMEM; + + hx->input_dev->name = "Himax HX852x"; + hx->input_dev->id.bustype = BUS_I2C; + hx->input_dev->open = hx852x_input_open; + hx->input_dev->close = hx852x_input_close; + + i2c_set_clientdata(client, hx); + input_set_drvdata(hx->input_dev, hx); + + hx->supplies[0].supply = "vcca"; + hx->supplies[1].supply = "vccd"; + error = devm_regulator_bulk_get(dev, ARRAY_SIZE(hx->supplies), hx->supplies); + if (error) + return dev_err_probe(dev, error, "failed to get regulators\n"); + + hx->reset_gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(hx->reset_gpiod)) + return dev_err_probe(dev, PTR_ERR(hx->reset_gpiod), + "failed to get reset gpio\n"); + + error = devm_request_threaded_irq(dev, client->irq, NULL, hx852x_interrupt, + IRQF_ONESHOT | IRQF_NO_AUTOEN, NULL, hx); + if (error) + return dev_err_probe(dev, error, "failed to request irq %d", client->irq); + + error = hx852x_read_config(hx); + if (error) + return error; + + input_set_capability(hx->input_dev, EV_ABS, ABS_MT_POSITION_X); + input_set_capability(hx->input_dev, EV_ABS, ABS_MT_POSITION_Y); + input_set_abs_params(hx->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0); + + touchscreen_parse_properties(hx->input_dev, true, &hx->props); + error = hx852x_parse_properties(hx); + if (error) + return error; + + hx->input_dev->keycode = hx->keycodes; + hx->input_dev->keycodemax = hx->keycount; + hx->input_dev->keycodesize = sizeof(hx->keycodes[0]); + for (i = 0; i < hx->keycount; i++) + input_set_capability(hx->input_dev, EV_KEY, hx->keycodes[i]); + + error = input_mt_init_slots(hx->input_dev, hx->max_fingers, + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); + if (error) + return dev_err_probe(dev, error, "failed to init MT slots\n"); + + error = input_register_device(hx->input_dev); + if (error) + return dev_err_probe(dev, error, "failed to register input device\n"); + + return 0; +} + +static int hx852x_suspend(struct device *dev) +{ + struct hx852x *hx = dev_get_drvdata(dev); + + guard(mutex)(&hx->input_dev->mutex); + + if (input_device_enabled(hx->input_dev)) + return hx852x_stop(hx); + + return 0; +} + +static int hx852x_resume(struct device *dev) +{ + struct hx852x *hx = dev_get_drvdata(dev); + + guard(mutex)(&hx->input_dev->mutex); + + if (input_device_enabled(hx->input_dev)) + return hx852x_start(hx); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(hx852x_pm_ops, hx852x_suspend, hx852x_resume); + +#ifdef CONFIG_OF +static const struct of_device_id hx852x_of_match[] = { + { .compatible = "himax,hx852es" }, + { } +}; +MODULE_DEVICE_TABLE(of, hx852x_of_match); +#endif + +static struct i2c_driver hx852x_driver = { + .probe = hx852x_probe, + .driver = { + .name = "himax_hx852x", + .pm = pm_sleep_ptr(&hx852x_pm_ops), + .of_match_table = of_match_ptr(hx852x_of_match), + }, +}; +module_i2c_driver(hx852x_driver); + +MODULE_DESCRIPTION("Himax HX852x(ES) Touchscreen Driver"); +MODULE_AUTHOR("Jonathan Albrieux <jonathan.albrieux@gmail.com>"); +MODULE_AUTHOR("Stephan Gerhold <stephan@gerhold.net>"); +MODULE_LICENSE("GPL"); |