[PATCH v2 6/8] Input: sx8654 - add sx8650 support

Richard Leitner
2018-10-17T16:02:53Z

The sx8654 and sx8650 are quite similar, therefore add support for the
sx8650 within the sx8654 driver.

Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
---
drivers/input/touchscreen/sx8654.c | 193 +++++++++++++++++++++++++++++++++----
1 file changed, 173 insertions(+), 20 deletions(-)

diff --git a/drivers/input/touchscreen/sx8654.c b/drivers/input/touchscreen/sx8654.c
index afa4da138fe9..4939863efbef 100644
--- a/drivers/input/touchscreen/sx8654.c
+++ b/drivers/input/touchscreen/sx8654.c
@@ -29,7 +29,7 @@

#include <linux/input.h>
#include <linux/module.h>
-#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
@@ -44,9 +44,11 @@
#define I2C_REG_IRQSRC 0x23
#define I2C_REG_SOFTRESET 0x3f

+#define I2C_REG_SX8650_STAT 0x05
+#define SX8650_STAT_CONVIRQ 0x80
+
/* commands */
#define CMD_READ_REGISTER 0x40
-#define CMD_MANUAL 0xc0
#define CMD_PENTRG 0xe0

/* value for I2C_REG_SOFTRESET */
@@ -58,6 +60,7 @@

/* bits for RegTouch1 */
#define CONDIRQ 0x20
+#define RPDNT_100K 0x00
#define FILT_7SA 0x03

/* bits for I2C_REG_CHANMASK */
@@ -71,14 +74,122 @@
/* power delay: lower nibble of CTRL0 register */
#define POWDLY_1_1MS 0x0b

+/* for sx8650, as we have no pen release IRQ there: timeout in ns following the
+ * last PENIRQ after which we assume the pen is lifted.
+ */
+#define SX8650_PENIRQ_TIMEOUT msecs_to_jiffies(10)
+
#define MAX_12BIT ((1 << 12) - 1)
+#define MAX_I2C_READ_LEN 10 /* see datasheet section 5.1.5 */
+
+/* channel definition */
+#define CH_X 0x00
+#define CH_Y 0x01
+
+struct sx865x_data {
+ u8 cmd_manual;
+ u8 chan_mask;
+ u8 has_irq_penrelease;
+ u8 has_reg_irqmask;
+ irq_handler_t irqh;
+};

struct sx8654 {
struct input_dev *input;
struct i2c_client *client;
struct gpio_desc *gpio_reset;
+
+ spinlock_t lock; /* for input reporting from irq/timer */
+ struct timer_list timer;
+
+ const struct sx865x_data *data;
};

+static inline void sx865x_penrelease(struct sx8654 *ts)
+{
+ struct input_dev *input_dev = ts->input;
+
+ input_report_key(input_dev, BTN_TOUCH, 0);
+ input_sync(input_dev);
+}
+
+static void sx865x_penrelease_timer_handler(struct timer_list *t)
+{
+ struct sx8654 *ts = from_timer(ts, t, timer);
+ unsigned long flags;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ sx865x_penrelease(ts);
+ spin_unlock_irqrestore(&ts->lock, flags);
+ dev_dbg(&ts->client->dev, "penrelease by timer\n");
+}
+
+static irqreturn_t sx8650_irq(int irq, void *handle)
+{
+ struct sx8654 *ts = handle;
+ struct device *dev = &ts->client->dev;
+ int len, i;
+ unsigned long flags;
+ u8 stat;
+ u16 x, y;
+ u8 data[MAX_I2C_READ_LEN];
+ u16 ch;
+ u16 chdata;
+ u8 readlen = hweight32(ts->data->chan_mask) * 2;
+
+ stat = i2c_smbus_read_byte_data(ts->client, CMD_READ_REGISTER
+ | I2C_REG_SX8650_STAT);
+
+ if (!(stat & SX8650_STAT_CONVIRQ)) {
+ dev_dbg(dev, "%s ignore stat [0x%02x]", __func__, stat);
+ return IRQ_HANDLED;
+ }
+
+ len = i2c_master_recv(ts->client, data, readlen);
+ if (len != readlen) {
+ dev_dbg(dev, "ignore short recv (%d)\n", len);
+ return IRQ_HANDLED;
+ }
+
+ spin_lock_irqsave(&ts->lock, flags);
+
+ x = 0;
+ y = 0;
+ for (i = 0; (i + 1) < len; i++) {
+ chdata = data[i] << 8;
+ i++;
+ chdata += data[i];
+
+ if (unlikely(chdata == 0xFFFF)) {
+ dev_dbg(dev, "invalid qualified data @ %d\n", i);
+ continue;
+ } else if (unlikely(chdata & 0x8000)) {
+ dev_warn(dev, "hibit @ %d [0x%04x]\n", i, chdata);
+ continue;
+ }
+
+ ch = chdata >> 12;
+ if (ch == CH_X)
+ x = chdata & MAX_12BIT;
+ else if (ch == CH_Y)
+ y = chdata & MAX_12BIT;
+ else
+ dev_warn(dev, "unknown channel %d [0x%04x]\n", ch,
+ chdata);
+ }
+
+ input_report_abs(ts->input, ABS_X, x);
+ input_report_abs(ts->input, ABS_Y, y);
+ input_report_key(ts->input, BTN_TOUCH, 1);
+ input_sync(ts->input);
+ dev_dbg(dev, "point(%4d,%4d)\n", x, y);
+
+ mod_timer(&ts->timer, jiffies + SX8650_PENIRQ_TIMEOUT);
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
static irqreturn_t sx8654_irq(int irq, void *handle)
{
struct sx8654 *sx8654 = handle;
@@ -127,6 +238,22 @@ static irqreturn_t sx8654_irq(int irq, void *handle)
return IRQ_HANDLED;
}

+static const struct sx865x_data sx8650_data = {
+ .cmd_manual = 0xb0,
+ .has_irq_penrelease = 0,
+ .has_reg_irqmask = 0,
+ .chan_mask = (CONV_X | CONV_Y),
+ .irqh = sx8650_irq,
+};
+
+static const struct sx865x_data sx8654_data = {
+ .cmd_manual = 0xc0,
+ .has_irq_penrelease = 1,
+ .has_reg_irqmask = 1,
+ .chan_mask = (CONV_X | CONV_Y),
+ .irqh = sx8654_irq,
+};
+
static int sx8654_reset(struct sx8654 *ts)
{
int err;
@@ -182,13 +309,13 @@ static void sx8654_close(struct input_dev *dev)
disable_irq(client->irq);

/* enable manual mode mode */
- error = i2c_smbus_write_byte(client, CMD_MANUAL);
+ error = i2c_smbus_write_byte(client, sx8654->data->cmd_manual);
if (error) {
dev_err(&client->dev, "writing command CMD_MANUAL failed");
return;
}

- error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0, 0);
+ error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0, RATE_MANUAL);
if (error) {
dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
return;
@@ -221,6 +348,20 @@ static int sx8654_probe(struct i2c_client *client,
}
dev_dbg(&client->dev, "got GPIO reset pin\n");

+ sx8654->data = of_device_get_match_data(&client->dev);
+ if (!sx8654->data)
+ sx8654->data = (const struct sx865x_data *)id->driver_data;
+ if (!sx8654->data) {
+ dev_err(&client->dev, "invalid or missing device data\n");
+ return -EINVAL;
+ }
+
+ if (!sx8654->data->has_irq_penrelease) {
+ dev_dbg(&client->dev, "use timer for penrelease\n");
+ timer_setup(&sx8654->timer, sx865x_penrelease_timer_handler, 0);
+ spin_lock_init(&sx8654->lock);
+ }
+
input = devm_input_allocate_device(&client->dev);
if (!input)
return -ENOMEM;
@@ -248,29 +389,31 @@ static int sx8654_probe(struct i2c_client *client,
}

error = i2c_smbus_write_byte_data(client, I2C_REG_CHANMASK,
- CONV_X | CONV_Y);
+ sx8654->data->chan_mask);
if (error) {
dev_err(&client->dev, "writing to I2C_REG_CHANMASK failed");
return error;
}

- error = i2c_smbus_write_byte_data(client, I2C_REG_IRQMASK,
- IRQ_PENTOUCH_TOUCHCONVDONE |
- IRQ_PENRELEASE);
- if (error) {
- dev_err(&client->dev, "writing to I2C_REG_IRQMASK failed");
- return error;
+ if (sx8654->data->has_reg_irqmask) {
+ error = i2c_smbus_write_byte_data(client, I2C_REG_IRQMASK,
+ IRQ_PENTOUCH_TOUCHCONVDONE |
+ IRQ_PENRELEASE);
+ if (error) {
+ dev_err(&client->dev, "writing I2C_REG_IRQMASK failed");
+ return error;
+ }
}

error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH1,
- CONDIRQ | FILT_7SA);
+ CONDIRQ | RPDNT_100K | FILT_7SA);
if (error) {
dev_err(&client->dev, "writing to I2C_REG_TOUCH1 failed");
return error;
}

error = devm_request_threaded_irq(&client->dev, client->irq,
- NULL, sx8654_irq,
+ NULL, sx8654->data->irqh,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
client->name, sx8654);
if (error) {
@@ -292,18 +435,28 @@ static int sx8654_probe(struct i2c_client *client,

#ifdef CONFIG_OF
static const struct of_device_id sx8654_of_match[] = {
- { .compatible = "semtech,sx8654", },
- { .compatible = "semtech,sx8655", },
- { .compatible = "semtech,sx8656", },
- { },
+ {
+ .compatible = "semtech,sx8650",
+ .data = &sx8650_data,
+ }, {
+ .compatible = "semtech,sx8654",
+ .data = &sx8654_data,
+ }, {
+ .compatible = "semtech,sx8655",
+ .data = &sx8654_data,
+ }, {
+ .compatible = "semtech,sx8656",
+ .data = &sx8654_data,
+ }, {},
};
MODULE_DEVICE_TABLE(of, sx8654_of_match);
#endif

static const struct i2c_device_id sx8654_id_table[] = {
- { "semtech_sx8654", 0 },
- { "semtech_sx8655", 0 },
- { "semtech_sx8656", 0 },
+ { .name = "semtech_sx8650", .driver_data = (long)&sx8650_data },
+ { .name = "semtech_sx8654", .driver_data = (long)&sx8654_data },
+ { .name = "semtech_sx8655", .driver_data = (long)&sx8654_data },
+ { .name = "semtech_sx8656", .driver_data = (long)&sx8654_data },
{ },
};
MODULE_DEVICE_TABLE(i2c, sx8654_id_table);
--
2.11.0