Input: elo - add support for non-pressure-sensitive touchscreens

- Use the touch status bit rather than the pressure bits to
  distinguish a BTN_TOUCH event. Non-pressure-sensitive touchscreens
  always report full pressure
- Report ABS_PRESSURE information only if the touchscreen supports it

Signed-off-by: Shaun Jackman <sjackman@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/touchscreen/elo.c b/drivers/input/touchscreen/elo.c
index fe6e1a428674b0b8bbcb074ba5e70e06ebb076e3..ab565335ee44131a69830fc9ac47b1213f58ce14 100644 (file)
--- a/drivers/input/touchscreen/elo.c
+++ b/drivers/input/touchscreen/elo.c
@@ -23,6 +23,7 @@
 #include <linux/input.h>
 #include <linux/serio.h>
 #include <linux/init.h>
+#include <linux/ctype.h>
 
 #define DRIVER_DESC    "Elo serial touchscreen driver"
 
@@ -36,9 +37,17 @@ MODULE_LICENSE("GPL");
 
 #define ELO_MAX_LENGTH         10
 
+#define ELO10_PACKET_LEN       8
+#define ELO10_TOUCH            0x03
+#define ELO10_PRESSURE         0x80
+
 #define ELO10_LEAD_BYTE                'U'
 
+#define ELO10_ID_CMD           'i'
+
 #define ELO10_TOUCH_PACKET     'T'
+#define ELO10_ACK_PACKET       'A'
+#define ELI10_ID_PACKET                'I'
 
 /*
  * Per-touchscreen data.
@@ -47,10 +56,14 @@ MODULE_LICENSE("GPL");
 struct elo {
        struct input_dev *dev;
        struct serio *serio;
+       struct mutex cmd_mutex;
+       struct completion cmd_done;
        int id;
        int idx;
+       unsigned char expected_packet;
        unsigned char csum;
        unsigned char data[ELO_MAX_LENGTH];
+       unsigned char response[ELO10_PACKET_LEN];
        char phys[32];
 };
 
@@ -75,16 +88,29 @@ static void elo_process_data_10(struct elo *elo, unsigned char data, struct pt_r
                                         data, elo->csum);
                                break;
                        }
-                       if (elo->data[1] != ELO10_TOUCH_PACKET) {
-                               pr_debug(elo: "unexpected packet: 0x%02x\n", elo->data[1]);
+                       if (elo->data[1] != elo->expected_packet) {
+                               if (elo->data[1] != ELO10_TOUCH_PACKET)
+                                       pr_debug("elo: unexpected packet: 0x%02x\n",
+                                                elo->data[1]);
                                break;
                        }
-                       input_regs(dev, regs);
-                       input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
-                       input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
-                       input_report_abs(dev, ABS_PRESSURE, (elo->data[8] << 8) | elo->data[7]);
-                       input_report_key(dev, BTN_TOUCH, elo->data[8] || elo->data[7]);
-                       input_sync(dev);
+                       if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) {
+                               input_regs(dev, regs);
+                               input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
+                               input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
+                               if (elo->data[2] & ELO10_PRESSURE)
+                                       input_report_abs(dev, ABS_PRESSURE,
+                                                       (elo->data[8] << 8) | elo->data[7]);
+                               input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
+                               input_sync(dev);
+                       } else if (elo->data[1] == ELO10_ACK_PACKET) {
+                               if (elo->data[2] == '0')
+                                       elo->expected_packet = ELO10_TOUCH_PACKET;
+                               complete(&elo->cmd_done);
+                       } else {
+                               memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
+                               elo->expected_packet = ELO10_ACK_PACKET;
+                       }
                        break;
        }
        elo->csum += data;
@@ -184,6 +210,68 @@ static irqreturn_t elo_interrupt(struct serio *serio,
        return IRQ_HANDLED;
 }
 
+static int elo_command_10(struct elo *elo, unsigned char *packet)
+{
+       int rc = -1;
+       int i;
+       unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
+
+       mutex_lock(&elo->cmd_mutex);
+
+       serio_pause_rx(elo->serio);
+       elo->expected_packet = toupper(packet[0]);
+       init_completion(&elo->cmd_done);
+       serio_continue_rx(elo->serio);
+
+       if (serio_write(elo->serio, ELO10_LEAD_BYTE))
+               goto out;
+
+       for (i = 0; i < ELO10_PACKET_LEN; i++) {
+               csum += packet[i];
+               if (serio_write(elo->serio, packet[i]))
+                       goto out;
+       }
+
+       if (serio_write(elo->serio, csum))
+               goto out;
+
+       wait_for_completion_timeout(&elo->cmd_done, HZ);
+
+       if (elo->expected_packet == ELO10_TOUCH_PACKET) {
+               /* We are back in reporting mode, the command was ACKed */
+               memcpy(packet, elo->response, ELO10_PACKET_LEN);
+               rc = 0;
+       }
+
+ out:
+       mutex_unlock(&elo->cmd_mutex);
+       return rc;
+}
+
+static int elo_setup_10(struct elo *elo)
+{
+       static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
+       struct input_dev *dev = elo->dev;
+       unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
+
+       if (elo_command_10(elo, packet))
+               return -1;
+
+       dev->id.version = (packet[5] << 8) | packet[4];
+
+       input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
+       input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
+       if (packet[3] & ELO10_PRESSURE)
+               input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
+
+       printk(KERN_INFO "elo: %sTouch touchscreen, fw: %02x.%02x, "
+               "features: %x02x, controller: 0x%02x\n",
+               elo_types[(packet[1] -'0') & 0x03],
+               packet[5], packet[4], packet[3], packet[7]);
+
+       return 0;
+}
+
 /*
  * elo_disconnect() is the opposite of elo_connect()
  */
@@ -222,6 +310,9 @@ static int elo_connect(struct serio *serio, struct serio_driver *drv)
        elo->serio = serio;
        elo->id = serio->id.id;
        elo->dev = input_dev;
+       elo->expected_packet = ELO10_TOUCH_PACKET;
+       mutex_init(&elo->cmd_mutex);
+       init_completion(&elo->cmd_done);
        snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
 
        input_dev->private = elo;
@@ -236,12 +327,17 @@ static int elo_connect(struct serio *serio, struct serio_driver *drv)
        input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
        input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
 
+       serio_set_drvdata(serio, elo);
+       err = serio_open(serio, drv);
+       if (err)
+               goto fail2;
+
        switch (elo->id) {
 
                case 0: /* 10-byte protocol */
-                       input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
-                       input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
-                       input_set_abs_params(input_dev, ABS_PRESSURE, 0, 255, 0, 0);
+                       if (elo_setup_10(elo))
+                               goto fail3;
+
                        break;
 
                case 1: /* 6-byte protocol */
@@ -258,12 +354,6 @@ static int elo_connect(struct serio *serio, struct serio_driver *drv)
                        break;
        }
 
-       serio_set_drvdata(serio, elo);
-
-       err = serio_open(serio, drv);
-       if (err)
-               goto fail2;
-
        err = input_register_device(elo->dev);
        if (err)
                goto fail3;