[PATCH] input: Add ROHM BU21023/24 Dual touch support resistive touchscreens

[PATCH] input: Add ROHM BU21023/24 Dual touch support resistive touchscreens

[Yoichi Yuasa]

Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
---
 drivers/input/touchscreen/Kconfig        |   11 +
 drivers/input/touchscreen/Makefile       |    1 +
 drivers/input/touchscreen/rohm_bu21023.c |  791 ++++++++++++++++++++++++++++++
 drivers/input/touchscreen/rohm_bu21023.h |  255 ++++++++++
 4 files changed, 1058 insertions(+)
 create mode 100644 drivers/input/touchscreen/rohm_bu21023.c
 create mode 100644 drivers/input/touchscreen/rohm_bu21023.h

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 6bb9a7d..9ae5c88 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -950,4 +950,15 @@ config TOUCHSCREEN_ZFORCE
 	  To compile this driver as a module, choose M here: the
 	  module will be called zforce_ts.
 
+config TOUCHSCREEN_ROHM_BU21023
+	tristate "ROHM BU21023/24 Dual touch support resistive touchscreens"
+	depends on I2C
+	help
+	  Say Y here if you have a touchscreen using ROHM BU21023/24.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called bu21023_ts.
+
 endif
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 4be94fc..af766d0 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_TOUCHSCREEN_USB_COMPOSITE)	+= usbtouchscreen.o
 obj-$(CONFIG_TOUCHSCREEN_PCAP)		+= pcap_ts.o
 obj-$(CONFIG_TOUCHSCREEN_PENMOUNT)	+= penmount.o
 obj-$(CONFIG_TOUCHSCREEN_PIXCIR)	+= pixcir_i2c_ts.o
+obj-$(CONFIG_TOUCHSCREEN_ROHM_BU21023)	+= rohm_bu21023.o
 obj-$(CONFIG_TOUCHSCREEN_S3C2410)	+= s3c2410_ts.o
 obj-$(CONFIG_TOUCHSCREEN_ST1232)	+= st1232.o
 obj-$(CONFIG_TOUCHSCREEN_STMPE)		+= stmpe-ts.o
diff --git a/drivers/input/touchscreen/rohm_bu21023.c b/drivers/input/touchscreen/rohm_bu21023.c
new file mode 100644
index 0000000..317d59b
--- /dev/null
+++ b/drivers/input/touchscreen/rohm_bu21023.c
@@ -0,0 +1,791 @@
+/*
+ * ROHM BU21023/24 Dual touch support resistive touch screen driver
+ * Copyright (C) 2012 ROHM CO.,LTD.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/hrtimer.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "rohm_bu21023.h"
+
+struct rohm_ts_point {
+	unsigned int x;
+	unsigned int y;
+};
+
+struct rohm_ts_data {
+	struct i2c_client *client;
+	struct input_dev *input_dev;
+
+	int use_irq;
+	struct hrtimer hrtimer;
+	struct workqueue_struct *workqueue;
+	struct work_struct work;
+
+	unsigned int untouch_count;
+	unsigned int single_touch_count;
+	unsigned int dual_touch_count;
+	unsigned int prev_touch_report;
+};
+
+/*
+ * rohm_i2c_burst_read - execute combined I2C message for ROHM BU21023/24
+ * @adap: Handle to I2C bus
+ * @msgs: combined messages to execute
+ * @num: Number of messages to be executed.
+ *
+ * Returns negative errno, else the number of messages executed.
+ *
+ * Note
+ * In BU21023/24 burst read, stop condition is needed after "address write".
+ * Therefore, transmission is performed in 2 steps.
+ */
+static inline int rohm_i2c_burst_read(struct i2c_adapter *adap,
+				      struct i2c_msg *msgs, int num)
+{
+	int ret, i;
+
+	if (!adap->algo->master_xfer) {
+		dev_dbg(&adap->dev, "I2C level transfers not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	i2c_lock_adapter(adap);
+
+	for (i = 0; i < num; i++) {
+		ret = __i2c_transfer(adap, &msgs[i], 1);
+		if (ret < 0)
+			break;
+
+		ret = i;
+	}
+
+	i2c_unlock_adapter(adap);
+
+	return ret;
+}
+
+static int rohm_ts_manual_calibration(struct rohm_ts_data *ts)
+{
+	struct i2c_client *client = ts->client;
+	struct device *dev = &client->dev;
+	struct i2c_msg msg[2];
+	u8 buf[33];
+	u8 addr_buf;		/* burst read start address */
+
+	int retry;
+	bool success = false;
+	bool first_time = true;
+	bool calibration_done;
+
+	u8 reg1, reg2, reg3;
+	u8 reg1_orig, reg2_orig, reg3_orig;
+
+	s32 val;
+
+	int calib_x = 0, calib_y = 0;
+	int reg_x, reg_y;
+	int err_x, err_y;
+
+	int ret;
+	int i;
+
+	addr_buf = PRM1_X_H;
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf = &addr_buf;
+
+	msg[1].addr = client->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = sizeof(buf);
+	msg[1].buf = buf;
+
+#define READ_CALIB_BUF(reg)	((u16)buf[((reg) - PRM1_X_H)])
+
+	reg1_orig = i2c_smbus_read_byte_data(client, CALIBRATION_REG1);
+	reg2_orig = i2c_smbus_read_byte_data(client, CALIBRATION_REG2);
+	reg3_orig = i2c_smbus_read_byte_data(client, CALIBRATION_REG3);
+
+	if (ts->use_irq)
+		disable_irq(client->irq);
+
+	i2c_smbus_write_byte_data(client, INT_MASK,
+				  COORD_UPDATE | SLEEP_IN | SLEEP_OUT |
+				  PROGRAM_LOAD_DONE);
+
+	i2c_smbus_write_byte_data(client, TEST1, DUALTOUCH_STABILIZE_ON);
+
+	for (retry = 0; retry < CALIBRATION_RETRY_MAX; retry++) {
+		/* wait 2 sampling for update */
+		mdelay(2 * SAMPLING_DELAY);
+
+		ret = rohm_i2c_burst_read(client->adapter, msg, 2);
+		if (!ret) {
+			dev_err(dev, "I2C transfer error\n");
+			return ret;
+		}
+
+		if (READ_CALIB_BUF(TOUCH) & TOUCH_DETECT)
+			continue;
+
+		if (first_time) {
+			/* generate calibration parameter */
+			calib_x =
+			    (READ_CALIB_BUF(PRM1_X_H) << 2 |
+			     READ_CALIB_BUF(PRM1_X_L)) - AXIS_OFFSET;
+			calib_y =
+			    (READ_CALIB_BUF(PRM1_Y_H) << 2 |
+			     READ_CALIB_BUF(PRM1_Y_L)) - AXIS_OFFSET;
+
+			i2c_smbus_write_byte_data(client, TEST1,
+						  DUALTOUCH_STABILIZE_ON |
+						  DUALTOUCH_REG_ON);
+
+			first_time = false;
+		} else {
+			/* generate adjustment parameter */
+			err_x = READ_CALIB_BUF(PRM1_X_H) << 2 |
+			    READ_CALIB_BUF(PRM1_X_L);
+			err_y = READ_CALIB_BUF(PRM1_Y_H) << 2 |
+			    READ_CALIB_BUF(PRM1_Y_L);
+
+			/* X axis ajust */
+			if (err_x <= 4)
+				calib_x -= AXIS_ADJUST;
+			else if (err_x >= 60)
+				calib_x += AXIS_ADJUST;
+
+			/* Y axis ajust */
+			if (err_y <= 4)
+				calib_y -= AXIS_ADJUST;
+			else if (err_y >= 60)
+				calib_y += AXIS_ADJUST;
+		}
+
+		/* generate calibration setting value */
+		reg_x = calib_x + ((calib_x & 0x200) << 1);
+		reg_y = calib_y + ((calib_y & 0x200) << 1);
+
+		/* convert for register format */
+		reg1 = reg_x >> 3;
+		reg2 = (reg_y & 0x7) << 4 | (reg_x & 0x7);
+		reg3 = reg_y >> 3;
+
+		i2c_smbus_write_byte_data(client, CALIBRATION_REG1, reg1);
+		i2c_smbus_write_byte_data(client, CALIBRATION_REG2, reg2);
+		i2c_smbus_write_byte_data(client, CALIBRATION_REG3, reg3);
+
+		/*
+		 * force calibration sequcence
+		 */
+		i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
+					  FORCE_CALIBRATION_OFF);
+
+		i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
+					  FORCE_CALIBRATION_ON);
+
+		/* clear all interrupts */
+		i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
+
+		/*
+		 * Wait for the status change of calibration, max 10 sampling
+		 */
+		calibration_done = false;
+
+		for (i = 0; i < 10; i++) {
+			mdelay(SAMPLING_DELAY);
+
+			val = i2c_smbus_read_byte_data(client, TOUCH_GESTURE);
+			if (!(val & CALIBRATION_MASK)) {
+				calibration_done = true;
+				break;
+			}
+		}
+
+		if (calibration_done) {
+			val = i2c_smbus_read_byte_data(client, INT_STATUS);
+			if (val == CALIBRATION_DONE) {
+				success = true;
+				break;
+			}
+		} else
+			dev_warn(dev, "Calibration timeout\n");
+	}
+
+	if (!success) {
+		i2c_smbus_write_byte_data(client, CALIBRATION_REG1, reg1_orig);
+		i2c_smbus_write_byte_data(client, CALIBRATION_REG2, reg2_orig);
+		i2c_smbus_write_byte_data(client, CALIBRATION_REG3, reg3_orig);
+
+		/* calibration data enable */
+		i2c_smbus_write_byte_data(client, TEST1,
+					  DUALTOUCH_STABILIZE_ON |
+					  DUALTOUCH_REG_ON);
+
+		/* wait 10 sampling */
+		mdelay(10 * SAMPLING_DELAY);
+
+		dev_warn(dev, "Failed to manual calibration\n");
+		ret = -EBUSY;
+	} else {
+		dev_dbg(dev, "Manual calibration done\n");
+		ret = 0;
+	}
+
+	i2c_smbus_write_byte_data(client, INT_MASK,
+				  COORD_UPDATE | CALIBRATION_DONE |
+				  SLEEP_IN | SLEEP_OUT |
+				  PROGRAM_LOAD_DONE | ERROR);
+
+	/* Clear all interrupts */
+	i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
+
+	if (ts->use_irq)
+		enable_irq(client->irq);
+
+	return ret;
+}
+
+static unsigned long inactive_polling_interval[2] = { 1, 0 };
+static unsigned long active_polling_interval[2] = { 0, 10000000 };
+
+module_param_array(inactive_polling_interval, ulong, NULL, S_IRUGO | S_IWUSR);
+module_param_array(active_polling_interval, ulong, NULL, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(inactive_polling_interval,
+		 "Polling interval for un-touch detection");
+MODULE_PARM_DESC(active_polling_interval,
+		 "Polling interval for touch detection");
+
+#define INACTIVE_POLLING_INTERVAL_KTIME	\
+	ktime_set(inactive_polling_interval[0], inactive_polling_interval[1])
+#define ACTIVE_POLLING_INTERVAL_KTIME	\
+	ktime_set(active_polling_interval[0], active_polling_interval[1])
+
+static unsigned int untouch_threshold[3] = { 0, 1, 5 };
+static unsigned int single_touch_threshold[3] = { 0, 0, 4 };
+static unsigned int dual_touch_threshold[3] = { 10, 8, 0 };
+
+module_param_array(untouch_threshold, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(single_touch_threshold, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(dual_touch_threshold, uint, NULL, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(untouch_threshold, "Thresholds for un-touch detection");
+MODULE_PARM_DESC(single_touch_threshold,
+		 "Thresholds for single touch detection");
+MODULE_PARM_DESC(dual_touch_threshold, "Thresholds for dual touch detection");
+
+static void rohm_ts_work_func(struct work_struct *work)
+{
+	struct rohm_ts_data *ts = container_of(work, struct rohm_ts_data, work);
+	struct i2c_client *client = ts->client;
+	struct input_dev *input_dev = ts->input_dev;
+	struct device *dev = &client->dev;
+	struct i2c_msg msg[2];
+	u16 addr = client->addr;
+	u8 addr_buf;
+	u8 buf[10];		/* for 0x20-0x29 */
+
+	struct rohm_ts_point tp1, tp2;
+	u8 touch_flags;
+	unsigned int threshold;
+	int touch_report = -1;
+	unsigned int prev_touch_report = ts->prev_touch_report;
+	bool next_sensing_immediately = false;
+
+	int ret;
+
+	i2c_smbus_write_byte_data(client, INT_MASK,
+				  COORD_UPDATE | CALIBRATION_DONE |
+				  SLEEP_OUT | SLEEP_IN | PROGRAM_LOAD_DONE |
+				  ERROR);
+
+	/* Clear all interrupts */
+	i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
+
+	addr_buf = POS_X1_H;
+	msg[0].addr = addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf = &addr_buf;
+
+	msg[1].addr = addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = sizeof(buf);
+	msg[1].buf = buf;
+
+#define READ_POS_BUF(reg)	((u16)buf[((reg) - POS_X1_H)])
+
+	ret = rohm_i2c_burst_read(client->adapter, msg, 2);
+	if (ret < 0) {
+		dev_err(dev, "I2C transfer error\n");
+		return;
+	}
+
+	touch_flags = READ_POS_BUF(TOUCH_GESTURE) & TOUCH_MASK;
+	if (touch_flags) {
+		next_sensing_immediately = true;
+
+		/* generate coordinates */
+		tp1.x = (READ_POS_BUF(POS_X1_H) << 2) | READ_POS_BUF(POS_X1_L);
+		tp1.y = (READ_POS_BUF(POS_Y1_H) << 2) | READ_POS_BUF(POS_Y1_L);
+		tp2.x = (READ_POS_BUF(POS_X2_H) << 2) | READ_POS_BUF(POS_X2_L);
+		tp2.y = (READ_POS_BUF(POS_Y2_H) << 2) | READ_POS_BUF(POS_Y2_L);
+
+		switch (touch_flags) {
+		case SINGLE_TOUCH:
+			ts->untouch_count = 0;
+			ts->single_touch_count++;
+			ts->dual_touch_count = 0;
+
+			threshold = single_touch_threshold[prev_touch_report];
+			if (ts->single_touch_count > threshold)
+				touch_report = 1;
+
+			if (touch_report == 1) {
+				if (tp2.x != 0 && tp2.y != 0) {
+					tp1.x = tp2.x;
+					tp1.y = tp2.y;
+					tp2.x = 0;
+					tp2.y = 0;
+				}
+			}
+			break;
+		case DUAL_TOUCH:
+			ts->untouch_count = 0;
+			ts->single_touch_count = 0;
+			ts->dual_touch_count++;
+
+			threshold = dual_touch_threshold[prev_touch_report];
+			if (ts->dual_touch_count > threshold)
+				touch_report = 2;
+			break;
+		default:
+			dev_err(dev,
+				"Three or more touches are not supported\n");
+			break;
+		}
+	} else {
+		ts->untouch_count++;
+
+		threshold = untouch_threshold[prev_touch_report];
+		if (ts->untouch_count > threshold) {
+			ts->untouch_count = 0;
+			ts->single_touch_count = 0;
+			ts->dual_touch_count = 0;
+
+			touch_report = 0;
+		} else if (prev_touch_report > 0) {
+			next_sensing_immediately = true;
+		}
+	}
+
+	switch (touch_report) {
+	case 0:
+		input_mt_sync(input_dev);
+
+		input_sync(input_dev);
+		ts->prev_touch_report = touch_report;
+		break;
+	case 1:
+		input_report_abs(input_dev, ABS_MT_POSITION_X, tp1.x);
+		input_report_abs(input_dev, ABS_MT_POSITION_Y, tp1.y);
+		input_mt_sync(input_dev);
+
+		input_sync(input_dev);
+		ts->prev_touch_report = touch_report;
+		break;
+	case 2:
+		input_report_abs(input_dev, ABS_MT_POSITION_X, tp1.x);
+		input_report_abs(input_dev, ABS_MT_POSITION_Y, tp1.y);
+		input_mt_sync(input_dev);
+		input_report_abs(input_dev, ABS_MT_POSITION_X, tp2.x);
+		input_report_abs(input_dev, ABS_MT_POSITION_Y, tp2.y);
+		input_mt_sync(input_dev);
+
+		input_sync(input_dev);
+		ts->prev_touch_report = touch_report;
+		break;
+	default:
+		break;
+	}
+
+	/* set next sensing time */
+	if (next_sensing_immediately) {
+		hrtimer_start(&ts->hrtimer,
+			      ACTIVE_POLLING_INTERVAL_KTIME, HRTIMER_MODE_REL);
+	} else {
+		if (READ_POS_BUF(TOUCH_GESTURE) & CALIBRATION_REQUEST)
+			rohm_ts_manual_calibration(ts);
+
+		if (ts->use_irq) {
+			i2c_smbus_write_byte_data(client, INT_MASK,
+						  CALIBRATION_DONE |
+						  SLEEP_OUT | SLEEP_IN |
+						  PROGRAM_LOAD_DONE);
+		} else {
+			hrtimer_start(&ts->hrtimer,
+				      INACTIVE_POLLING_INTERVAL_KTIME,
+				      HRTIMER_MODE_REL);
+		}
+	}
+}
+
+static enum hrtimer_restart rohm_ts_timer_func(struct hrtimer *hrtimer)
+{
+	struct rohm_ts_data *ts =
+	    container_of(hrtimer, struct rohm_ts_data, hrtimer);
+
+	queue_work(ts->workqueue, &ts->work);
+
+	return HRTIMER_NORESTART;
+}
+
+static irqreturn_t rohm_ts_irq_handler(int irq, void *dev_id)
+{
+	struct rohm_ts_data *ts = dev_id;
+
+	queue_work(ts->workqueue, &ts->work);
+
+	return IRQ_HANDLED;
+}
+
+static int rohm_ts_load_firmware(struct i2c_client *client,
+				 const char *firmware_name)
+{
+	struct device *dev = &client->dev;
+	const struct firmware *firmware = NULL;
+	s32 status;
+	int blocks, remainder, retry, offset;
+	int ret;
+	int i;
+
+	ret = request_firmware(&firmware, firmware_name, dev);
+	if (ret) {
+		dev_err(dev, "Unable to open firmware %s\n", firmware_name);
+		return ret;
+	}
+
+	blocks = firmware->size / FIRMWARE_BLOCK_SIZE;
+	remainder = firmware->size % FIRMWARE_BLOCK_SIZE;
+
+	i2c_smbus_write_byte_data(client, INT_MASK,
+				  COORD_UPDATE | CALIBRATION_DONE |
+				  SLEEP_IN | SLEEP_OUT);
+
+	for (retry = 0; retry < FIRMWARE_RETRY_MAX; retry++) {
+		i2c_smbus_write_byte_data(client, COMMON_SETUP1,
+					  COMMON_SETUP1_DEFAULT);
+		i2c_smbus_write_byte_data(client, EX_ADDR_H, 0);
+		i2c_smbus_write_byte_data(client, EX_ADDR_L, 0);
+
+		offset = 0;
+
+		/* firmware load to the device */
+		for (i = 0; i < blocks; i++) {
+			i2c_smbus_write_i2c_block_data(client, EX_WDAT,
+						       FIRMWARE_BLOCK_SIZE,
+						       &firmware->data[offset]);
+			offset += FIRMWARE_BLOCK_SIZE;
+		}
+
+		if (remainder)
+			i2c_smbus_write_i2c_block_data(client, EX_WDAT,
+						       remainder,
+						       &firmware->data[offset]);
+
+		/* check formware load result */
+		status = i2c_smbus_read_byte_data(client, INT_STATUS);
+
+		/* clear all interrupts */
+		i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
+
+		if (status == PROGRAM_LOAD_DONE)
+			break;
+
+		dev_warn(dev, "Retry firmware load\n");
+
+		/* settings for retry */
+		i2c_smbus_write_byte_data(client, EX_WDAT, 0);
+	}
+
+	i2c_smbus_write_byte_data(client, INT_MASK,
+				  COORD_UPDATE | CALIBRATION_DONE |
+				  SLEEP_IN | SLEEP_OUT |
+				  PROGRAM_LOAD_DONE | ERROR);
+
+	release_firmware(firmware);
+
+	if (retry >= FIRMWARE_RETRY_MAX)
+		return -EBUSY;
+
+	return 0;
+}
+
+static bool swap_xy;
+module_param(swap_xy, bool, S_IRUGO);
+MODULE_PARM_DESC(swap_xy, "Swap X-axis and Y-axis");
+
+static bool inv_x;
+module_param(inv_x, bool, S_IRUGO);
+MODULE_PARM_DESC(inv_x, "Invert X-axis");
+
+static bool inv_y;
+module_param(inv_y, bool, S_IRUGO);
+MODULE_PARM_DESC(inv_y, "Invert Y-axis");
+
+static int rohm_ts_device_init(struct i2c_client *client)
+{
+	u8 val;
+	int ret;
+
+	/*
+	 * Wait 200usec for reset
+	 */
+	udelay(200);
+
+	/* Release analog reset */
+	ret = i2c_smbus_write_byte_data(client, SYSTEM, ANALOG_POWER_ON);
+	if (ret < 0)
+		return ret;
+
+	/* Waiting for the analog warm-up, max. 200usec */
+	udelay(200);
+
+	/* clear all interrupts */
+	i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
+
+	val = MAF_1SAMPLE;
+	if (swap_xy)
+		val |= SWAP_XY;
+	if (inv_x)
+		val |= INV_X;
+	if (inv_y)
+		val |= INV_Y;
+
+	i2c_smbus_write_byte_data(client, EX_WDAT, 0);
+	i2c_smbus_write_byte_data(client, COMMON_SETUP1, 0);
+	i2c_smbus_write_byte_data(client, COMMON_SETUP2, val);
+	i2c_smbus_write_byte_data(client, COMMON_SETUP3,
+				  SEL_TBL_DEFAULT | EN_GESTURE | EN_MULTI);
+	i2c_smbus_write_byte_data(client, THRESHOLD_GESTURE,
+				  THRESHOLD_GESTURE_DEFAULT);
+
+	i2c_smbus_write_byte_data(client, INTERVAL_TIME, INTERVAL_TIME_DEFAULT);
+	i2c_smbus_write_byte_data(client, CPU_FREQ, CPU_FREQ_10MHZ);
+	i2c_smbus_write_byte_data(client, PRM_SWOFF_TIME,
+				  PRM_SWOFF_TIME_DEFAULT);
+	i2c_smbus_write_byte_data(client, ADC_CTRL, ADC_DIV_DEFAULT);
+	i2c_smbus_write_byte_data(client, ADC_WAIT, ADC_WAIT_DEFAULT);
+
+	/*
+	 * Panel setup, these values change with the panel.
+	 */
+	i2c_smbus_write_byte_data(client, STEP_X, STEP_X_DEFAULT);
+	i2c_smbus_write_byte_data(client, STEP_Y, STEP_Y_DEFAULT);
+	i2c_smbus_write_byte_data(client, OFFSET_X, OFFSET_X_DEFAULT);
+	i2c_smbus_write_byte_data(client, OFFSET_Y, OFFSET_Y_DEFAULT);
+	i2c_smbus_write_byte_data(client, THRESHOLD_TOUCH,
+				  THRESHOLD_TOUCH_DEFAULT);
+	i2c_smbus_write_byte_data(client, EVR_XY, EVR_XY_DEFAULT);
+	i2c_smbus_write_byte_data(client, EVR_X, EVR_X_DEFAULT);
+	i2c_smbus_write_byte_data(client, EVR_Y, EVR_Y_DEFAULT);
+
+	/* Fixed value settings */
+	i2c_smbus_write_byte_data(client, CALIBRATION_ADJUST,
+				  CALIBRATION_ADJUST_DEFAULT);
+	i2c_smbus_write_byte_data(client, SWCONT, SWCONT_DEFAULT);
+	i2c_smbus_write_byte_data(client, TEST1,
+				  DUALTOUCH_STABILIZE_ON | DUALTOUCH_REG_ON);
+
+	ret = rohm_ts_load_firmware(client, BU21023_FIRMWARE_NAME);
+	if (ret) {
+		dev_err(&client->dev, "Failed to firmware load\n");
+		return ret;
+	}
+
+	/*
+	 * Manual calibration results are not changed in same environment.
+	 * If the force calibration is performed,
+	 * the controller will not require calibration request interrupt
+	 * when the typical values are set to the calibration registers.
+	 */
+	i2c_smbus_write_byte_data(client, CALIBRATION_REG1,
+				  CALIBRATION_REG1_DEFAULT);
+	i2c_smbus_write_byte_data(client, CALIBRATION_REG2,
+				  CALIBRATION_REG2_DEFAULT);
+	i2c_smbus_write_byte_data(client, CALIBRATION_REG3,
+				  CALIBRATION_REG3_DEFAULT);
+
+	i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
+				  FORCE_CALIBRATION_OFF);
+	i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
+				  FORCE_CALIBRATION_ON);
+
+	/* Clear all interrupts */
+	i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
+
+	/* Enable coordinates update interrupt */
+	i2c_smbus_write_byte_data(client, INT_MASK,
+				  CALIBRATION_DONE | SLEEP_OUT | SLEEP_IN |
+				  PROGRAM_LOAD_DONE);
+
+	i2c_smbus_write_byte_data(client, ERR_MASK,
+				  PROGRAM_LOAD_ERR | CPU_TIMEOUT | ADC_TIMEOUT);
+
+	/* controller CPU power on */
+	i2c_smbus_write_byte_data(client, SYSTEM,
+				  CPU_POWER_ON | ANALOG_POWER_ON);
+
+	return 0;
+}
+
+static int rohm_bu21023_i2c_probe(struct i2c_client *client,
+				  const struct i2c_device_id *id)
+{
+	struct rohm_ts_data *ts;
+	struct device *dev = &client->dev;
+	struct input_dev *input_dev;
+	int ret;
+
+	ts = kzalloc(sizeof(struct rohm_ts_data), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	INIT_WORK(&ts->work, rohm_ts_work_func);
+
+	ts->client = client;
+	i2c_set_clientdata(client, ts);
+
+	ret = rohm_ts_device_init(client);
+	if (ret) {
+		dev_err(dev, "Failed to device initialization\n");
+		goto err_ts_free_exit;
+	}
+
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		ret = -ENOMEM;
+		dev_err(dev, "Failed to allocate input device\n");
+		goto err_ts_free_exit;
+	}
+
+	input_dev->name = BU21023_NAME;
+	input_dev->id.bustype = BUS_I2C;
+	input_dev->dev.parent = &client->dev;
+
+	ts->input_dev = input_dev;
+
+	set_bit(EV_SYN, input_dev->evbit);
+	set_bit(EV_KEY, input_dev->evbit);
+	set_bit(EV_ABS, input_dev->evbit);
+
+	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
+			     ROHM_TS_ABS_X_MIN, ROHM_TS_ABS_X_MAX, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
+			     ROHM_TS_ABS_Y_MIN, ROHM_TS_ABS_Y_MAX, 0, 0);
+
+	ret = input_register_device(input_dev);
+	if (ret) {
+		dev_err(dev, "Unable to register input device\n");
+		goto err_input_free_device_exit;
+	}
+
+	ts->workqueue = create_singlethread_workqueue("rohm_ts_wq");
+	if (!ts->workqueue) {
+		dev_err(dev, "Cannot create workqueue\n");
+		ret = -ENOMEM;
+		goto err_input_unregister_device_exit;
+	}
+
+	if (client->irq) {
+		ret = request_irq(client->irq, rohm_ts_irq_handler,
+				  IRQF_TRIGGER_FALLING, client->name, ts);
+
+		/* If the request IRQ failed, use polling mode */
+		if (!ret)
+			ts->use_irq = 1;
+	}
+
+	hrtimer_init(&ts->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	ts->hrtimer.function = rohm_ts_timer_func;
+	if (!ts->use_irq)
+		hrtimer_start(&ts->hrtimer, INACTIVE_POLLING_INTERVAL_KTIME,
+			      HRTIMER_MODE_REL);
+
+	dev_info(dev, "%s mode\n", ts->use_irq ? "interrupt" : "polling");
+
+	return 0;
+
+err_input_unregister_device_exit:
+	input_unregister_device(input_dev);
+
+err_input_free_device_exit:
+	input_free_device(input_dev);
+
+err_ts_free_exit:
+	kfree(ts);
+
+	return ret;
+}
+
+static int rohm_bu21023_i2c_remove(struct i2c_client *client)
+{
+	struct rohm_ts_data *ts = i2c_get_clientdata(client);
+
+	if (ts->use_irq)
+		free_irq(client->irq, ts);
+	else
+		hrtimer_cancel(&ts->hrtimer);
+
+	if (ts->workqueue)
+		destroy_workqueue(ts->workqueue);
+
+	input_unregister_device(ts->input_dev);
+
+	i2c_smbus_write_byte_data(client, SYSTEM,
+				  ANALOG_POWER_ON | CPU_POWER_OFF);
+
+	i2c_smbus_write_byte_data(client, SYSTEM,
+				  ANALOG_POWER_OFF | CPU_POWER_OFF);
+
+	kfree(ts);
+
+	return 0;
+}
+
+static const struct i2c_device_id rohm_bu21023_i2c_id[] = {
+	{BU21023_NAME, 0},
+	{},
+};
+
+MODULE_DEVICE_TABLE(i2c, rohm_bu21023_i2c_id);
+
+static struct i2c_driver rohm_bu21023_i2c_driver = {
+	.driver = {
+		   .name = BU21023_NAME,
+		   },
+	.probe = rohm_bu21023_i2c_probe,
+	.remove = rohm_bu21023_i2c_remove,
+	.id_table = rohm_bu21023_i2c_id,
+};
+
+module_i2c_driver(rohm_bu21023_i2c_driver);
+
+MODULE_DESCRIPTION("ROHM BU21023/24 Touchscreen driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/input/touchscreen/rohm_bu21023.h b/drivers/input/touchscreen/rohm_bu21023.h
new file mode 100644
index 0000000..2db32848
--- /dev/null
+++ b/drivers/input/touchscreen/rohm_bu21023.h
@@ -0,0 +1,255 @@
+/*
+ * ROHM BU21023/24 Dual touch support resistive touch screen driver
+ * Copyright (C) 2012 ROHM CO.,LTD.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+#ifndef _BU21023_TS_H
+#define _BU21023_TS_H
+
+#define BU21023_NAME		"bu21023_ts"
+#define BU21023_FIRMWARE_NAME	"bu21023.bin"
+
+#define AXIS_ADJUST		4
+#define AXIS_OFFSET		8
+
+#define FIRMWARE_BLOCK_SIZE	32
+#define FIRMWARE_RETRY_MAX	4
+
+#define SAMPLING_DELAY		12	/* msec */
+
+#define CALIBRATION_RETRY_MAX	6
+
+#define ROHM_TS_ABS_X_MIN	40
+#define ROHM_TS_ABS_X_MAX	990
+#define ROHM_TS_ABS_Y_MIN	160
+#define ROHM_TS_ABS_Y_MAX	920
+
+/*
+ * BU21023GUL/BU21023MUV/BU21024FV-M registers map
+ */
+#define VADOUT_YP_H		0x00
+#define VADOUT_YP_L		0x01
+#define VADOUT_XP_H		0x02
+#define VADOUT_XP_L		0x03
+#define VADOUT_YN_H		0x04
+#define VADOUT_YN_L		0x05
+#define VADOUT_XN_H		0x06
+#define VADOUT_XN_L		0x07
+
+#define PRM1_X_H		0x08
+#define PRM1_X_L		0x09
+#define PRM1_Y_H		0x0a
+#define PRM1_Y_L		0x0b
+#define PRM2_X_H		0x0c
+#define PRM2_X_L		0x0d
+#define PRM2_Y_H		0x0e
+#define PRM2_Y_L		0x0f
+
+#define MLT_PRM_MONI_X		0x10
+#define MLT_PRM_MONI_Y		0x11
+
+#define DEBUG_MONI_1		0x12
+#define DEBUG_MONI_2		0x13
+
+#define VADOUT_ZX_H		0x14
+#define VADOUT_ZX_L		0x15
+#define VADOUT_ZY_H		0x16
+#define VADOUT_ZY_L		0x17
+
+#define Z_PARAM_H		0x18
+#define Z_PARAM_L		0x19
+
+/*
+ * Value for VADOUT_*_L
+ */
+#define VADOUT_L_MASK		0x01
+
+/*
+ * Value for PRM*_*_L
+ */
+#define PRM_L_MASK		0x01
+
+#define POS_X1_H		0x20
+#define POS_X1_L		0x21
+#define POS_Y1_H		0x22
+#define POS_Y1_L		0x23
+#define POS_X2_H		0x24
+#define POS_X2_L		0x25
+#define POS_Y2_H		0x26
+#define POS_Y2_L		0x27
+
+/*
+ * Value for POS_*_L
+ */
+#define POS_L_MASK		0x01
+
+#define TOUCH			0x28
+#define TOUCH_DETECT		0x01
+
+#define TOUCH_GESTURE		0x29
+#define SINGLE_TOUCH		0x01
+#define DUAL_TOUCH		0x03
+#define TOUCH_MASK		0x03
+#define CALIBRATION_REQUEST	0x04
+#define CALIBRATION_STATUS	0x08
+#define CALIBRATION_MASK	0x0c
+#define GESTURE_SPREAD		0x10
+#define GESTURE_PINCH		0x20
+#define GESTURE_ROTATE_R	0x40
+#define GESTURE_ROTATE_L	0x80
+
+#define INT_STATUS		0x2a
+#define INT_MASK		0x3d
+#define INT_CLEAR		0x3e
+
+/*
+ * Values for INT_*
+ */
+#define COORD_UPDATE		0x01
+#define CALIBRATION_DONE	0x02
+#define SLEEP_IN		0x04
+#define SLEEP_OUT		0x08
+#define PROGRAM_LOAD_DONE	0x10
+#define ERROR			0x80
+
+#define ERR_STATUS		0x2b
+#define ERR_MASK		0x3f
+
+/*
+ * Values for ERR_*
+ */
+#define ADC_TIMEOUT		0x01
+#define CPU_TIMEOUT		0x02
+#define CALIBRATION_ERR		0x04
+#define PROGRAM_LOAD_ERR	0x10
+
+#define COMMON_SETUP1			0x30
+#define PROGRAM_LOAD_HOST		0x02
+#define PROGRAM_LOAD_EEPROM		0x03
+#define CENSOR_4PORT			0x04
+#define CENSOR_8PORT			0x00	/* Not supported by BU21023 */
+#define CALIBRATION_TYPE_DEFAULT	0x08
+#define CALIBRATION_TYPE_SPECIAL	0x00
+#define INT_ACTIVE_HIGH			0x10
+#define INT_ACTIVE_LOW			0x00
+#define AUTO_CALIBRATION		0x40
+#define MANUAL_CALIBRATION		0x00
+#define COMMON_SETUP1_DEFAULT		0x4e
+
+#define COMMON_SETUP2		0x31
+#define MAF_NONE		0x00
+#define MAF_1SAMPLE		0x01
+#define MAF_3SAMPLES		0x02
+#define MAF_5SAMPLES		0x03
+#define INV_Y			0x04
+#define INV_X			0x08
+#define SWAP_XY			0x10
+
+#define COMMON_SETUP3		0x32
+#define EN_SLEEP		0x01
+#define EN_MULTI		0x02
+#define EN_GESTURE		0x04
+#define EN_INTVL		0x08
+#define SEL_STEP		0x10
+#define SEL_MULTI		0x20
+#define SEL_TBL_DEFAULT		0x40
+
+#define INTERVAL_TIME		0x33
+#define INTERVAL_TIME_DEFAULT	0x10
+
+#define STEP_X			0x34
+#define STEP_X_DEFAULT		0x41
+
+#define STEP_Y			0x35
+#define STEP_Y_DEFAULT		0x8d
+
+#define OFFSET_X		0x38
+#define OFFSET_X_DEFAULT	0x0c
+
+#define OFFSET_Y		0x39
+#define OFFSET_Y_DEFAULT	0x0c
+
+#define THRESHOLD_TOUCH		0x3a
+#define THRESHOLD_TOUCH_DEFAULT	0xa0
+
+#define THRESHOLD_GESTURE		0x3b
+#define THRESHOLD_GESTURE_DEFAULT	0x17
+
+#define SYSTEM			0x40
+#define ANALOG_POWER_ON		0x01
+#define ANALOG_POWER_OFF	0x00
+#define CPU_POWER_ON		0x02
+#define CPU_POWER_OFF		0x00
+
+#define FORCE_CALIBRATION	0x42
+#define FORCE_CALIBRATION_ON	0x01
+#define FORCE_CALIBRATION_OFF	0x00
+
+#define CPU_FREQ		0x50	/* 10 / (reg + 1) MHz */
+#define CPU_FREQ_10MHZ		0x00
+#define CPU_FREQ_5MHZ		0x01
+#define CPU_FREQ_1MHZ		0x09
+
+#define EEPROM_ADDR		0x51
+
+#define CALIBRATION_ADJUST		0x52
+#define CALIBRATION_ADJUST_DEFAULT	0x00
+
+#define THRESHOLD_SLEEP_IN	0x53
+
+#define EVR_XY			0x56
+#define EVR_XY_DEFAULT		0x10
+
+#define PRM_SWOFF_TIME		0x57
+#define PRM_SWOFF_TIME_DEFAULT	0x04
+
+#define PROGRAM_VERSION		0x5f
+
+#define ADC_CTRL		0x60
+#define ADC_DIV_MASK		0x1f	/* The minimum value is 4 */
+#define ADC_DIV_DEFAULT		0x08
+
+#define ADC_WAIT		0x61
+#define ADC_WAIT_DEFAULT	0x0a
+
+#define SWCONT			0x62
+#define SWCONT_DEFAULT		0x0f
+
+#define EVR_X			0x63
+#define EVR_X_DEFAULT		0x86
+
+#define EVR_Y			0x64
+#define EVR_Y_DEFAULT		0x64
+
+#define TEST1			0x65
+#define DUALTOUCH_STABILIZE_ON	0x01
+#define DUALTOUCH_STABILIZE_OFF	0x00
+#define DUALTOUCH_REG_ON	0x20
+#define DUALTOUCH_REG_OFF	0x00
+
+#define CALIBRATION_REG1		0x68
+#define CALIBRATION_REG1_DEFAULT	0xd9
+
+#define CALIBRATION_REG2		0x69
+#define CALIBRATION_REG2_DEFAULT	0x36
+
+#define CALIBRATION_REG3		0x6a
+#define CALIBRATION_REG3_DEFAULT	0x32
+
+#define EX_ADDR_H		0x70
+#define EX_ADDR_L		0x71
+#define EX_WDAT			0x72
+#define EX_RDAT			0x73
+#define EX_CHK_SUM1		0x74
+#define EX_CHK_SUM2		0x75
+#define EX_CHK_SUM3		0x76
+
+#endif /* _BU21023_TS_H */
-- 
1.7.9.5

Re: [PATCH] input: Add ROHM BU21023/24 Dual touch support resistive touchscreens

[Pramod Gurav]

Hi Yoichi,

On Thursday 31 July 2014 04:24 PM, Yoichi Yuasa wrote:
> Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
> ---
>  drivers/input/touchscreen/Kconfig        |   11 +
>  drivers/input/touchscreen/Makefile       |    1 +
>  drivers/input/touchscreen/rohm_bu21023.c |  791 ++++++++++++++++++++++++++++++
>  drivers/input/touchscreen/rohm_bu21023.h |  255 ++++++++++
>  4 files changed, 1058 insertions(+)

[snip]

> +
> +/*
> + * rohm_i2c_burst_read - execute combined I2C message for ROHM BU21023/24
> + * @adap: Handle to I2C bus
> + * @msgs: combined messages to execute
> + * @num: Number of messages to be executed.
> + *
> + * Returns negative errno, else the number of messages executed.
> + *
> + * Note
> + * In BU21023/24 burst read, stop condition is needed after "address write".
> + * Therefore, transmission is performed in 2 steps.
> + */
> +static inline int rohm_i2c_burst_read(struct i2c_adapter *adap,
> +				      struct i2c_msg *msgs, int num)
> +{
> +	int ret, i;
> +
> +	if (!adap->algo->master_xfer) {
> +		dev_dbg(&adap->dev, "I2C level transfers not supported\n");
Should it be dev_err?

> +		return -EOPNOTSUPP;
> +	}
> +
> +	i2c_lock_adapter(adap);
> +
> +	for (i = 0; i < num; i++) {
> +		ret = __i2c_transfer(adap, &msgs[i], 1);
.
[snip]
.
> +
> +	return 0;
> +}
> +
> +static int rohm_bu21023_i2c_probe(struct i2c_client *client,
> +				  const struct i2c_device_id *id)
> +{
> +	struct rohm_ts_data *ts;
> +	struct device *dev = &client->dev;
> +	struct input_dev *input_dev;
> +	int ret;
> +
> +	ts = kzalloc(sizeof(struct rohm_ts_data), GFP_KERNEL);
Can you please move to managed resources? devm_kzalloc in this case?

> +	if (!ts)
> +		return -ENOMEM;
> +
> +	INIT_WORK(&ts->work, rohm_ts_work_func);
> +
> +	ts->client = client;
> +	i2c_set_clientdata(client, ts);
> +
> +	ret = rohm_ts_device_init(client);
> +	if (ret) {
> +		dev_err(dev, "Failed to device initialization\n");
> +		goto err_ts_free_exit;
> +	}
> +
> +	input_dev = input_allocate_device();
Same here as well. You can use devm_input_allocate_device here. These
helps in error handling and clean unbinding of driver.

> +	if (!input_dev) {
> +		ret = -ENOMEM;
> +		dev_err(dev, "Failed to allocate input device\n");
> +		goto err_ts_free_exit;
> +	}
> +
> +	input_dev->name = BU21023_NAME;
> +	input_dev->id.bustype = BUS_I2C;
> +	input_dev->dev.parent = &client->dev;
> +
> +	ts->input_dev = input_dev;
> +
> +	set_bit(EV_SYN, input_dev->evbit);
> +	set_bit(EV_KEY, input_dev->evbit);
> +	set_bit(EV_ABS, input_dev->evbit);
> +
> +	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
> +			     ROHM_TS_ABS_X_MIN, ROHM_TS_ABS_X_MAX, 0, 0);
> +	input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
> +			     ROHM_TS_ABS_Y_MIN, ROHM_TS_ABS_Y_MAX, 0, 0);
> +
> +	ret = input_register_device(input_dev);
> +	if (ret) {
> +		dev_err(dev, "Unable to register input device\n");
> +		goto err_input_free_device_exit;
> +	}
> +
> +	ts->workqueue = create_singlethread_workqueue("rohm_ts_wq");
> +	if (!ts->workqueue) {
> +		dev_err(dev, "Cannot create workqueue\n");
> +		ret = -ENOMEM;
> +		goto err_input_unregister_device_exit;
> +	}
> +
> +	if (client->irq) {
> +		ret = request_irq(client->irq, rohm_ts_irq_handler,
> +				  IRQF_TRIGGER_FALLING, client->name, ts);
Use devm_request_irq.
> +
> +		/* If the request IRQ failed, use polling mode */
> +		if (!ret)
> +			ts->use_irq = 1;
> +	}
> +
> +	hrtimer_init(&ts->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
> +	ts->hrtimer.function = rohm_ts_timer_func;
> +	if (!ts->use_irq)
> +		hrtimer_start(&ts->hrtimer, INACTIVE_POLLING_INTERVAL_KTIME,
> +			      HRTIMER_MODE_REL);
> +
> +	dev_info(dev, "%s mode\n", ts->use_irq ? "interrupt" : "polling");
> +
> +	return 0;
> +
> +err_input_unregister_device_exit:
> +	input_unregister_device(input_dev);
> +
> +err_input_free_device_exit:
> +	input_free_device(input_dev);
> +
> +err_ts_free_exit:
> +	kfree(ts);
> +
> +	return ret;
You can get rid of these lables with managed resources as they will be
release automatically when device is unbinded.

> +}
> +
> +static int rohm_bu21023_i2c_remove(struct i2c_client *client)
> +{
> +	struct rohm_ts_data *ts = i2c_get_clientdata(client);
> +
> +	if (ts->use_irq)
> +		free_irq(client->irq, ts);
Use of Managed resources will get rid of this as well.
> +	else
> +		hrtimer_cancel(&ts->hrtimer);
> +
> +	if (ts->workqueue)
> +		destroy_workqueue(ts->workqueue);
> +
> +	input_unregister_device(ts->input_dev);
This too.
> +
> +	i2c_smbus_write_byte_data(client, SYSTEM,
> +				  ANALOG_POWER_ON | CPU_POWER_OFF);
> +
> +	i2c_smbus_write_byte_data(client, SYSTEM,
> +				  ANALOG_POWER_OFF | CPU_POWER_OFF);
> +
> +	kfree(ts);
This too.
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id rohm_bu21023_i2c_id[] = {
> +	{BU21023_NAME, 0},
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, rohm_bu21023_i2c_id);
> +
> +static struct i2c_driver rohm_bu21023_i2c_driver = {
> +	.driver = {
> +		   .name = BU21023_NAME,
> +		   },
> +	.probe = rohm_bu21023_i2c_probe,
> +	.remove = rohm_bu21023_i2c_remove,
> +	.id_table = rohm_bu21023_i2c_id,
> +};
> +
> +module_i2c_driver(rohm_bu21023_i2c_driver);
> +
> +MODULE_DESCRIPTION("ROHM BU21023/24 Touchscreen driver");
> +MODULE_LICENSE("GPL");
Make it GPL v2.
MODULE_AUTHOR missing.

> diff --git a/drivers/input/touchscreen/rohm_bu21023.h b/drivers/input/touchscreen/rohm_bu21023.h
> new file mode 100644
> index 0000000..2db32848
> --- /dev/null
> +++ b/drivers/input/touchscreen/rohm_bu21023.h

[snip]

> 

Re: [PATCH] input: Add ROHM BU21023/24 Dual touch support resistive touchscreens

[Dmitry Torokhov]

Hi Yuichi,

On Thu, Jul 31, 2014 at 07:54:34PM +0900, Yoichi Yuasa wrote:
> Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>

I few high-level comments:

- please get rid of polling - it is not useful in production mode;
- switch to threaded interrupts so that you do not need to manage
  workqueue/work/timers;
- new drivers should use MT-B protocol with proper contact tracking. If device
  does not do good job at tracking contacts you can use input's core matching
algorithm (input_mt_assign_slots).
- please provide ST emulation as well (input_mt_report_pointer_emulation).
- the way you requesting firmware in probe path means you need to build
  firmware image into kernel or be careful how you pack it to avoid timeouts on
  boot. Since the device properties are not changing you might want to postpone
  that until somebody tries to open the device.
- please add error handling for IO operations.
- managed resources simplify the code.

Thanks.

-- 
Dmitry

Re: [PATCH] input: Add ROHM BU21023/24 Dual touch support resistive touchscreens

[Yoichi Yuasa]

Hi Pramod,

Thank you for your comments.

On Thu, 31 Jul 2014 17:24:42 +0530
Pramod Gurav <pramod.gurav@smartplayin.com> wrote:

> Hi Yoichi,
> 
> On Thursday 31 July 2014 04:24 PM, Yoichi Yuasa wrote:
> > Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
> > ---
> >  drivers/input/touchscreen/Kconfig        |   11 +
> >  drivers/input/touchscreen/Makefile       |    1 +
> >  drivers/input/touchscreen/rohm_bu21023.c |  791 ++++++++++++++++++++++++++++++
> >  drivers/input/touchscreen/rohm_bu21023.h |  255 ++++++++++
> >  4 files changed, 1058 insertions(+)
> 
[snip]
> > +static inline int rohm_i2c_burst_read(struct i2c_adapter *adap,
> > +				      struct i2c_msg *msgs, int num)
> > +{
> > +	int ret, i;
> > +
> > +	if (!adap->algo->master_xfer) {
> > +		dev_dbg(&adap->dev, "I2C level transfers not supported\n");
> Should it be dev_err?

Yes it is.

> > +static int rohm_bu21023_i2c_probe(struct i2c_client *client,
> > +				  const struct i2c_device_id *id)
> > +{
> > +	struct rohm_ts_data *ts;
> > +	struct device *dev = &client->dev;
> > +	struct input_dev *input_dev;
> > +	int ret;
> > +
> > +	ts = kzalloc(sizeof(struct rohm_ts_data), GFP_KERNEL);
> Can you please move to managed resources? devm_kzalloc in this case?

I'll move these to managed resources.

> > +
> > +MODULE_DESCRIPTION("ROHM BU21023/24 Touchscreen driver");
> > +MODULE_LICENSE("GPL");
> Make it GPL v2.
> MODULE_AUTHOR missing.

I'll try to contact the original author.

Thanks,

Yoichi

Re: [PATCH] input: Add ROHM BU21023/24 Dual touch support resistive touchscreens

[Yoichi Yuasa]

Hi Dmitry,

On Thu, 31 Jul 2014 10:16:55 -0700
Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:

> Hi Yuichi,
> 
> On Thu, Jul 31, 2014 at 07:54:34PM +0900, Yoichi Yuasa wrote:
> > Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
> 
> I few high-level comments:
> 
> - please get rid of polling - it is not useful in production mode;
> - switch to threaded interrupts so that you do not need to manage
>   workqueue/work/timers;
> - new drivers should use MT-B protocol with proper contact tracking. If device
>   does not do good job at tracking contacts you can use input's core matching
> algorithm (input_mt_assign_slots).
> - please provide ST emulation as well (input_mt_report_pointer_emulation).
> - the way you requesting firmware in probe path means you need to build
>   firmware image into kernel or be careful how you pack it to avoid timeouts on
>   boot. Since the device properties are not changing you might want to postpone
>   that until somebody tries to open the device.
> - please add error handling for IO operations.
> - managed resources simplify the code.

Thank you for your comments.
I'll try to update.

Thanks,

Yoichi