diff mbox series

[v3,3/4] input: cyttsp5: use raw i2c instead of regmap

Message ID 20250110-nekocwd-upstreaming-cyttsp5-v3-3-b33659c8effc@gmail.com (mailing list archive)
State New
Headers show
Series Input: cyttsp5 - improve error handling and remove regmap | expand

Commit Message

Vasiliy Doylov via B4 Relay Jan. 9, 2025, 9:37 p.m. UTC
From: "Vasiliy Doylov (NekoCWD)" <nekodevelopper@gmail.com>

Regmap always does operations against specific registers
and prevents doing raw i2c operations needed to handle some
hardware/firmware issues for some variants.
For example: on Huawei Mediapad T3 10 (huawei-agassi):
Some firmware variants doesn't work with mainline driver.
They starts in application mode and needs buffer flush (deassert_read).
Without flush it will always have value 2 in size reg.

Co-developed-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Vasiliy Doylov (NekoCWD) <nekodevelopper@gmail.com>
---
 drivers/input/touchscreen/cyttsp5.c | 228 ++++++++++++++++++++++--------------
 1 file changed, 143 insertions(+), 85 deletions(-)
diff mbox series

Patch

diff --git a/drivers/input/touchscreen/cyttsp5.c b/drivers/input/touchscreen/cyttsp5.c
index 4b73b1abc7e449b2dd0c453b816ce7887d9ddb0e..4860ce751c913c605d5f72dad66d1eba9825a900 100644
--- a/drivers/input/touchscreen/cyttsp5.c
+++ b/drivers/input/touchscreen/cyttsp5.c
@@ -20,7 +20,6 @@ 
 #include <linux/i2c.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
-#include <linux/regmap.h>
 #include <linux/unaligned.h>
 
 #define CYTTSP5_NAME				"cyttsp5"
@@ -68,6 +67,7 @@ 
 #define HID_BTN_REPORT_ID			0x3
 #define HID_APP_RESPONSE_REPORT_ID		0x1F
 #define HID_APP_OUTPUT_REPORT_ID		0x2F
+#define HID_BL_REPORT_ID			0xFF
 #define HID_BL_RESPONSE_REPORT_ID		0x30
 #define HID_BL_OUTPUT_REPORT_ID			0x40
 #define HID_RESPONSE_REPORT_ID			0xF0
@@ -206,7 +206,6 @@  struct cyttsp5 {
 	struct input_dev *input;
 	char phys[NAME_MAX];
 	int num_prv_rec;
-	struct regmap *regmap;
 	struct touchscreen_properties prop;
 	struct regulator_bulk_data supplies[2];
 };
@@ -219,16 +218,24 @@  struct cyttsp5 {
  */
 static int cyttsp5_read(struct cyttsp5 *ts, u8 *buf, u32 max)
 {
-	int error;
+	struct i2c_client *client = to_i2c_client(ts->dev);
+	struct i2c_msg msgs[2];
+	u8 msg_count = 1;
+	int rc;
 	u32 size;
-	u8 temp[2];
 
-	/* Read the frame to retrieve the size */
-	error = regmap_bulk_read(ts->regmap, HID_INPUT_REG, temp, sizeof(temp));
-	if (error)
-		return error;
+	if (!buf)
+		return -EINVAL;
 
-	size = get_unaligned_le16(temp);
+	msgs[0].addr = client->addr;
+	msgs[0].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
+	msgs[0].len = 2;
+	msgs[0].buf = buf;
+	rc = i2c_transfer(client->adapter, msgs, msg_count);
+	if (rc < 0 || rc != msg_count)
+		return (rc < 0) ? rc : -EIO;
+
+	size = get_unaligned_le16(&buf[0]);
 	/*
 	 * Before PIP 1.7, empty buffer is 0x0002
 	 * From PIP 1.7, empty buffer is 0xFFXX
@@ -239,33 +246,37 @@  static int cyttsp5_read(struct cyttsp5 *ts, u8 *buf, u32 max)
 	if (size > max)
 		return -EINVAL;
 
-	/* Get the real value */
-	return regmap_bulk_read(ts->regmap, HID_INPUT_REG, buf, size);
+	rc = i2c_master_recv(client, buf, size);
+
+	return (rc < 0) ? rc : rc != (int)size ? -EIO : 0;
 }
 
 static int cyttsp5_write(struct cyttsp5 *ts, unsigned int reg, u8 *data,
 			 size_t size)
 {
-	u8 cmd[HID_OUTPUT_MAX_CMD_SIZE];
+	u8 cmd[HID_OUTPUT_MAX_CMD_SIZE + 2];
+	struct i2c_client *client = to_i2c_client(ts->dev);
+	struct i2c_msg msgs[2];
+	u8 msg_count = 1;
+	int rc;
 
-	if (size + 1 > HID_OUTPUT_MAX_CMD_SIZE)
+	if (size > HID_OUTPUT_MAX_CMD_SIZE + 2)
 		return -E2BIG;
 
-	/* High bytes of register address needed as first byte of cmd */
-	cmd[0] = (reg >> 8) & 0xFF;
-
 	/* Copy the rest of the data */
 	if (data)
-		memcpy(&cmd[1], data, size);
+		memcpy(&cmd[0], data, size);
 
-	/*
-	 * The hardware wants to receive a frame with the address register
-	 * contained in the first two bytes. As the regmap_write function
-	 * add the register adresse in the frame, we use the low byte as
-	 * first frame byte for the address register and the first
-	 * data byte is the high register + left of the cmd to send
-	 */
-	return regmap_bulk_write(ts->regmap, reg & 0xFF, cmd, size + 1);
+	msgs[0].addr = client->addr;
+	msgs[0].flags = client->flags & I2C_M_TEN;
+	msgs[0].len = size;
+	msgs[0].buf = cmd;
+	rc = i2c_transfer(client->adapter, msgs, msg_count);
+
+	if (rc < 0 || rc != msg_count)
+		return (rc < 0) ? rc : -EIO;
+
+	return 0;
 }
 
 static void cyttsp5_get_touch_axis(int *axis, int size, int max, u8 *xy_data,
@@ -540,22 +551,29 @@  static int cyttsp5_get_sysinfo_regs(struct cyttsp5 *ts)
 	scd->len_x = get_unaligned_le16(&scd_dev->len_x);
 	scd->len_y = get_unaligned_le16(&scd_dev->len_y);
 
+	if (scd_dev->max_num_of_tch_per_refresh_cycle == 0)
+		return -EINVAL;
+
 	return 0;
 }
 
 static int cyttsp5_hid_output_get_sysinfo(struct cyttsp5 *ts)
 {
 	int rc;
-	u8 cmd[HID_OUTPUT_GET_SYSINFO_SIZE];
+	u8 cmd[HID_OUTPUT_GET_SYSINFO_SIZE + 2];
+
+	/* Set Output register */
+	memcpy(&cmd[0], &ts->hid_desc.output_register,
+			sizeof(ts->hid_desc.output_register));
 
 	/* HI bytes of Output register address */
-	put_unaligned_le16(HID_OUTPUT_GET_SYSINFO_SIZE, cmd);
-	cmd[2] = HID_APP_OUTPUT_REPORT_ID;
-	cmd[3] = 0x0; /* Reserved */
-	cmd[4] = HID_OUTPUT_GET_SYSINFO;
+	put_unaligned_le16(HID_OUTPUT_GET_SYSINFO_SIZE, &cmd[2]);
+	cmd[4] = HID_APP_OUTPUT_REPORT_ID;
+	cmd[5] = 0x0; /* Reserved */
+	cmd[6] = HID_OUTPUT_GET_SYSINFO;
 
 	rc = cyttsp5_write(ts, HID_OUTPUT_REG, cmd,
-			   HID_OUTPUT_GET_SYSINFO_SIZE);
+			   HID_OUTPUT_GET_SYSINFO_SIZE + 2);
 	if (rc) {
 		dev_err(ts->dev, "Failed to write command %d", rc);
 		return rc;
@@ -615,21 +633,25 @@  static int cyttsp5_power_control(struct cyttsp5 *ts, bool on)
 static int cyttsp5_hid_output_bl_launch_app(struct cyttsp5 *ts)
 {
 	int rc;
-	u8 cmd[HID_OUTPUT_BL_LAUNCH_APP_SIZE];
+	u8 cmd[HID_OUTPUT_BL_LAUNCH_APP_SIZE + 2];
 	u16 crc;
 
-	put_unaligned_le16(HID_OUTPUT_BL_LAUNCH_APP_SIZE, cmd);
-	cmd[2] = HID_BL_OUTPUT_REPORT_ID;
-	cmd[3] = 0x0; /* Reserved */
-	cmd[4] = HID_OUTPUT_BL_SOP;
-	cmd[5] = HID_OUTPUT_BL_LAUNCH_APP;
-	put_unaligned_le16(0x00, &cmd[6]);
-	crc = crc_itu_t(0xFFFF, &cmd[4], 4);
-	put_unaligned_le16(crc, &cmd[8]);
-	cmd[10] = HID_OUTPUT_BL_EOP;
+	/* Set Output register */
+	memcpy(&cmd[0], &ts->hid_desc.output_register,
+			sizeof(ts->hid_desc.output_register));
+
+	put_unaligned_le16(HID_OUTPUT_BL_LAUNCH_APP_SIZE, &cmd[2]);
+	cmd[4] = HID_BL_OUTPUT_REPORT_ID;
+	cmd[5] = 0x0; /* Reserved */
+	cmd[6] = HID_OUTPUT_BL_SOP;
+	cmd[7] = HID_OUTPUT_BL_LAUNCH_APP;
+	put_unaligned_le16(0x00, &cmd[8]);
+	crc = crc_itu_t(0xFFFF, &cmd[6], 4);
+	put_unaligned_le16(crc, &cmd[10]);
+	cmd[12] = HID_OUTPUT_BL_EOP;
 
 	rc = cyttsp5_write(ts, HID_OUTPUT_REG, cmd,
-			   HID_OUTPUT_BL_LAUNCH_APP_SIZE);
+			   HID_OUTPUT_BL_LAUNCH_APP_SIZE + 2);
 	if (rc) {
 		dev_err(ts->dev, "Failed to write command %d", rc);
 		return rc;
@@ -656,9 +678,12 @@  static int cyttsp5_get_hid_descriptor(struct cyttsp5 *ts,
 				      struct cyttsp5_hid_desc *desc)
 {
 	struct device *dev = ts->dev;
+	u8 cmd[2] = { 0 };
 	int rc;
 
-	rc = cyttsp5_write(ts, HID_DESC_REG, NULL, 0);
+	put_unaligned_le16(HID_DESC_REG, cmd);
+
+	rc = cyttsp5_write(ts, HID_DESC_REG, cmd, 2);
 	if (rc) {
 		dev_err(dev, "Failed to get HID descriptor, rc=%d\n", rc);
 		return rc;
@@ -739,19 +764,38 @@  static irqreturn_t cyttsp5_handle_irq(int irq, void *handle)
 	return IRQ_HANDLED;
 }
 
+static int cyttsp5_deassert_read(struct cyttsp5 *ts, u8 *buf, int size)
+{
+	struct i2c_client *client = to_i2c_client(ts->dev);
+	int rc;
+
+	if (!buf || !size || size > CY_I2C_DATA_SIZE)
+		return -EINVAL;
+
+	rc = i2c_master_recv(client, buf, size);
+
+	return (rc < 0) ? rc : rc != size ? -EIO : 0;
+}
+
 static int cyttsp5_deassert_int(struct cyttsp5 *ts)
 {
 	u16 size;
-	u8 buf[2];
+	u8 retry = 3;
 	int error;
 
-	error = regmap_bulk_read(ts->regmap, HID_INPUT_REG, buf, sizeof(buf));
-	if (error < 0)
-		return error;
+	do {
+		error = cyttsp5_deassert_read(ts, ts->input_buf, 2);
+		if (error < 0)
+			return error;
 
-	size = get_unaligned_le16(&buf[0]);
-	if (size == 2 || size == 0 || size >= CY_PIP_1P7_EMPTY_BUF)
-		return 0;
+		size = get_unaligned_le16(&ts->input_buf[0]);
+		if (size == 2 || size == 0 || size >= CY_PIP_1P7_EMPTY_BUF)
+			return 0;
+
+		error = cyttsp5_deassert_read(ts, ts->input_buf, size);
+		if (error < 0)
+			return error;
+	} while (retry--);
 
 	return -EINVAL;
 }
@@ -785,23 +829,35 @@  static int cyttsp5_startup(struct cyttsp5 *ts)
 	error = cyttsp5_deassert_int(ts);
 	if (error) {
 		dev_err(ts->dev, "Error on deassert int r=%d\n", error);
-		return -ENODEV;
+	}
+
+	error = cyttsp5_get_hid_descriptor(ts, &ts->hid_desc);
+	if (error < 0) {
+		dev_err(ts->dev, "Error on getting HID descriptor r=%d\n", error);
+		return error;
 	}
 
 	/*
 	 * Launch the application as the device starts in bootloader mode
 	 * because of a power-on-reset
 	 */
-	error = cyttsp5_hid_output_bl_launch_app(ts);
-	if (error < 0) {
-		dev_err(ts->dev, "Error on launch app r=%d\n", error);
-		return error;
-	}
+	if (ts->hid_desc.packet_id == HID_BL_REPORT_ID) {
+		error = cyttsp5_hid_output_bl_launch_app(ts);
+		if (error < 0) {
+			dev_err(ts->dev, "Error on launch app r=%d\n", error);
+			return error;
+		}
 
-	error = cyttsp5_get_hid_descriptor(ts, &ts->hid_desc);
-	if (error < 0) {
-		dev_err(ts->dev, "Error on getting HID descriptor r=%d\n", error);
-		return error;
+		error = cyttsp5_get_hid_descriptor(ts, &ts->hid_desc);
+		if (error < 0) {
+			dev_err(ts->dev, "Error on getting HID descriptor r=%d\n", error);
+			return error;
+		}
+
+		if (ts->hid_desc.packet_id == HID_BL_REPORT_ID) {
+			dev_err(ts->dev, "Error on launch app still in bootloader\n");
+			return -EPROTO;
+		}
 	}
 
 	error = cyttsp5_fill_all_touch(ts);
@@ -826,8 +882,7 @@  static void cyttsp5_cleanup(void *data)
 	regulator_bulk_disable(ARRAY_SIZE(ts->supplies), ts->supplies);
 }
 
-static int cyttsp5_probe(struct device *dev, struct regmap *regmap, int irq,
-			 const char *name)
+static struct cyttsp5 *cyttsp5_probe(struct device *dev, int irq, const char *name)
 {
 	struct cyttsp5 *ts;
 	struct cyttsp5_sysinfo *si;
@@ -835,10 +890,9 @@  static int cyttsp5_probe(struct device *dev, struct regmap *regmap, int irq,
 
 	ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
 	if (!ts)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	/* Initialize device info */
-	ts->regmap = regmap;
 	ts->dev = dev;
 	si = &ts->sysinfo;
 	dev_set_drvdata(dev, ts);
@@ -852,23 +906,23 @@  static int cyttsp5_probe(struct device *dev, struct regmap *regmap, int irq,
 					ts->supplies);
 	if (error) {
 		dev_err(ts->dev, "Failed to get regulators, error %d\n", error);
-		return error;
+		return ERR_PTR(error);
 	}
 
 	error = devm_add_action_or_reset(dev, cyttsp5_cleanup, ts);
 	if (error)
-		return error;
+		return ERR_PTR(error);
 
 	error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies), ts->supplies);
 	if (error) {
 		dev_err(ts->dev, "Failed to enable regulators, error %d\n", error);
-		return error;
+		return ERR_PTR(error);
 	}
 
 	ts->input = devm_input_allocate_device(dev);
 	if (!ts->input) {
 		dev_err(dev, "Error, failed to allocate input device\n");
-		return -ENODEV;
+		return ERR_PTR(-ENODEV);
 	}
 
 	ts->input->name = "cyttsp5";
@@ -881,7 +935,7 @@  static int cyttsp5_probe(struct device *dev, struct regmap *regmap, int irq,
 	if (IS_ERR(ts->reset_gpio)) {
 		error = PTR_ERR(ts->reset_gpio);
 		dev_err(dev, "Failed to request reset gpio, error %d\n", error);
-		return error;
+		return ERR_PTR(error);
 	}
 	gpiod_set_value_cansleep(ts->reset_gpio, 0);
 
@@ -889,22 +943,22 @@  static int cyttsp5_probe(struct device *dev, struct regmap *regmap, int irq,
 	msleep(20);
 
 	error = devm_request_threaded_irq(dev, irq, NULL, cyttsp5_handle_irq,
-					  IRQF_ONESHOT, name, ts);
+					  IRQF_TRIGGER_LOW | IRQF_ONESHOT, name, ts);
 	if (error) {
 		dev_err(dev, "unable to request IRQ\n");
-		return error;
+		return ERR_PTR(error);
 	}
 
 	error = cyttsp5_startup(ts);
 	if (error) {
 		dev_err(ts->dev, "Fail initial startup r=%d\n", error);
-		return error;
+		return ERR_PTR(error);
 	}
 
 	error = cyttsp5_parse_dt_key_code(dev);
 	if (error < 0) {
 		dev_err(ts->dev, "Error while parsing dts %d\n", error);
-		return error;
+		return ERR_PTR(error);
 	}
 
 	touchscreen_parse_properties(ts->input, true, &ts->prop);
@@ -913,25 +967,29 @@  static int cyttsp5_probe(struct device *dev, struct regmap *regmap, int irq,
 	for (i = 0; i < si->num_btns; i++)
 		__set_bit(si->key_code[i], ts->input->keybit);
 
-	return cyttsp5_setup_input_device(dev);
+	error = cyttsp5_setup_input_device(dev);
+	if (error < 0)
+		return ERR_PTR(error);
+
+	return ts;
 }
 
 static int cyttsp5_i2c_probe(struct i2c_client *client)
 {
-	struct regmap *regmap;
-	static const struct regmap_config config = {
-		.reg_bits = 8,
-		.val_bits = 8,
-	};
+	struct cyttsp5 *ts;
 
-	regmap = devm_regmap_init_i2c(client, &config);
-	if (IS_ERR(regmap)) {
-		dev_err(&client->dev, "regmap allocation failed: %ld\n",
-			PTR_ERR(regmap));
-		return PTR_ERR(regmap);
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "I2C functionality not Supported\n");
+		return -EIO;
 	}
 
-	return cyttsp5_probe(&client->dev, regmap, client->irq, client->name);
+	ts = cyttsp5_probe(&client->dev, client->irq, client->name);
+
+	if (IS_ERR(ts))
+		return PTR_ERR(ts);
+
+	i2c_set_clientdata(client, ts);
+	return 0;
 }
 
 static const struct of_device_id cyttsp5_of_match[] = {