Input: sx8654 - add sx8650 support

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>
Reviewed-by: Rob Herring <robh@kernel.org>
[dtor: use __be16 in sx8650_irq, add missing del_timer_sync]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 176 insertions, 20 deletions

diff --git a/drivers/input/touchscreen/sx8654.c b/drivers/input/touchscreen/sx8654.c
index 9e1777ed93a7..5f5af8eaecea 100644
--- a/drivers/input/touchscreen/sx8654.c
+++ b/drivers/input/touchscreen/sx8654.c
@@ -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 +74,121 @@
 /* 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;
+        bool has_irq_penrelease;
+        bool 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;
+        u16 ch;
+        u16 chdata;
+        __be16 data[MAX_I2C_READ_LEN / sizeof(__be16)];
+        u8 nchan = hweight32(ts->data->chan_mask);
+        u8 readlen = nchan * sizeof(*data);
+
+        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, (u8 *)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 < nchan; i++) {
+                chdata = be16_to_cpu(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;
@@ -179,14 +289,17 @@ static void sx8654_close(struct input_dev *dev)
 
         disable_irq(client->irq);
 
+        if (!sx8654->data->has_irq_penrelease)
+                del_timer_sync(&sx8654->timer);
+
         /* 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;
@@ -219,6 +332,20 @@ static int sx8654_probe(struct i2c_client *client,
         }
         dev_dbg(&client->dev, "got GPIO reset pin\n");
 
+        sx8654->data = 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;
@@ -246,29 +373,31 @@ 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) {
@@ -288,21 +417,48 @@ static int sx8654_probe(struct i2c_client *client,
         return 0;
 }
 
+static const struct sx865x_data sx8650_data = {
+        .cmd_manual             = 0xb0,
+        .has_irq_penrelease     = false,
+        .has_reg_irqmask        = false,
+        .chan_mask              = (CONV_X | CONV_Y),
+        .irqh                   = sx8650_irq,
+};
+
+static const struct sx865x_data sx8654_data = {
+        .cmd_manual             = 0xc0,
+        .has_irq_penrelease     = true,
+        .has_reg_irqmask        = true,
+        .chan_mask              = (CONV_X | CONV_Y),
+        .irqh                   = sx8654_irq,
+};
+
 #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);