input: ti_am33x_tsc: Order of TSC wires, made configurable

The current driver expected touchscreen input
wires(XP,XN,YP,YN) to be connected in a particular order.
Making changes to accept this as platform data.

Sebastian reworked the original patch and removed a lot of the not
required pieces.

Signed-off-by: Patil, Rachna <rachna@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
index 23d6a4dacc88d47cacf4874cb8133abb248cb3c5..2bdd66cd76a79569083c9c8f3a36a65b43c984c0 100644 (file)
--- a/drivers/input/touchscreen/ti_am335x_tsc.c
+++ b/drivers/input/touchscreen/ti_am335x_tsc.c
@@ -33,6 +33,13 @@
 #define SEQ_SETTLE             275
 #define MAX_12BIT              ((1 << 12) - 1)
 
+static const int config_pins[] = {
+       STEPCONFIG_XPP,
+       STEPCONFIG_XNN,
+       STEPCONFIG_YPP,
+       STEPCONFIG_YNN,
+};
+
 struct titsc {
        struct input_dev        *input;
        struct ti_tscadc_dev    *mfd_tscadc;
@@ -41,6 +48,9 @@ struct titsc {
        unsigned int            x_plate_resistance;
        bool                    pen_down;
        int                     steps_to_configure;
+       u32                     config_inp[4];
+       u32                     bit_xp, bit_xn, bit_yp, bit_yn;
+       u32                     inp_xp, inp_xn, inp_yp, inp_yn;
 };
 
 static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
@@ -54,6 +64,58 @@ static void titsc_writel(struct titsc *tsc, unsigned int reg,
        writel(val, tsc->mfd_tscadc->tscadc_base + reg);
 }
 
+static int titsc_config_wires(struct titsc *ts_dev)
+{
+       u32 analog_line[4];
+       u32 wire_order[4];
+       int i, bit_cfg;
+
+       for (i = 0; i < 4; i++) {
+               /*
+                * Get the order in which TSC wires are attached
+                * w.r.t. each of the analog input lines on the EVM.
+                */
+               analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4;
+               wire_order[i] = ts_dev->config_inp[i] & 0x0F;
+               if (WARN_ON(analog_line[i] > 7))
+                       return -EINVAL;
+               if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins)))
+                       return -EINVAL;
+       }
+
+       for (i = 0; i < 4; i++) {
+               int an_line;
+               int wi_order;
+
+               an_line = analog_line[i];
+               wi_order = wire_order[i];
+               bit_cfg = config_pins[wi_order];
+               if (bit_cfg == 0)
+                       return -EINVAL;
+               switch (wi_order) {
+               case 0:
+                       ts_dev->bit_xp = bit_cfg;
+                       ts_dev->inp_xp = an_line;
+                       break;
+
+               case 1:
+                       ts_dev->bit_xn = bit_cfg;
+                       ts_dev->inp_xn = an_line;
+                       break;
+
+               case 2:
+                       ts_dev->bit_yp = bit_cfg;
+                       ts_dev->inp_yp = an_line;
+                       break;
+               case 3:
+                       ts_dev->bit_yn = bit_cfg;
+                       ts_dev->inp_yn = an_line;
+                       break;
+               }
+       }
+       return 0;
+}
+
 static void titsc_step_config(struct titsc *ts_dev)
 {
        unsigned int    config;
@@ -64,18 +126,18 @@ static void titsc_step_config(struct titsc *ts_dev)
        total_steps = 2 * ts_dev->steps_to_configure;
 
        config = STEPCONFIG_MODE_HWSYNC |
-                       STEPCONFIG_AVG_16 | STEPCONFIG_XPP;
+                       STEPCONFIG_AVG_16 | ts_dev->bit_xp;
        switch (ts_dev->wires) {
        case 4:
-               config |= STEPCONFIG_INP_AN2 | STEPCONFIG_XNN;
+               config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
                break;
        case 5:
-               config |= STEPCONFIG_YNN |
-                               STEPCONFIG_INP_AN4 | STEPCONFIG_XNN |
-                               STEPCONFIG_YPP;
+               config |= ts_dev->bit_yn |
+                               STEPCONFIG_INP_AN4 | ts_dev->bit_xn |
+                               ts_dev->bit_yp;
                break;
        case 8:
-               config |= STEPCONFIG_INP_AN2 | STEPCONFIG_XNN;
+               config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
                break;
        }
 
@@ -86,18 +148,18 @@ static void titsc_step_config(struct titsc *ts_dev)
 
        config = 0;
        config = STEPCONFIG_MODE_HWSYNC |
-                       STEPCONFIG_AVG_16 | STEPCONFIG_YNN |
+                       STEPCONFIG_AVG_16 | ts_dev->bit_yn |
                        STEPCONFIG_INM_ADCREFM | STEPCONFIG_FIFO1;
        switch (ts_dev->wires) {
        case 4:
-               config |= STEPCONFIG_YPP;
+               config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
                break;
        case 5:
-               config |= STEPCONFIG_XPP | STEPCONFIG_INP_AN4 |
-                               STEPCONFIG_XNP | STEPCONFIG_YPN;
+               config |= ts_dev->bit_xp | STEPCONFIG_INP_AN4 |
+                               ts_dev->bit_xn | ts_dev->bit_yp;
                break;
        case 8:
-               config |= STEPCONFIG_YPP;
+               config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
                break;
        }
 
@@ -108,9 +170,9 @@ static void titsc_step_config(struct titsc *ts_dev)
 
        config = 0;
        /* Charge step configuration */
-       config = STEPCONFIG_XPP | STEPCONFIG_YNN |
+       config = ts_dev->bit_xp | ts_dev->bit_yn |
                        STEPCHARGE_RFP_XPUL | STEPCHARGE_RFM_XNUR |
-                       STEPCHARGE_INM_AN1 | STEPCHARGE_INP_AN1;
+                       STEPCHARGE_INM_AN1 | STEPCHARGE_INP(ts_dev->inp_yp);
 
        titsc_writel(ts_dev, REG_CHARGECONFIG, config);
        titsc_writel(ts_dev, REG_CHARGEDELAY, CHARGEDLY_OPENDLY);
@@ -118,13 +180,14 @@ static void titsc_step_config(struct titsc *ts_dev)
        config = 0;
        /* Configure to calculate pressure */
        config = STEPCONFIG_MODE_HWSYNC |
-                       STEPCONFIG_AVG_16 | STEPCONFIG_YPP |
-                       STEPCONFIG_XNN | STEPCONFIG_INM_ADCREFM;
+                       STEPCONFIG_AVG_16 | ts_dev->bit_yp |
+                       ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM |
+                       STEPCONFIG_INP(ts_dev->inp_xp);
        titsc_writel(ts_dev, REG_STEPCONFIG(total_steps + 1), config);
        titsc_writel(ts_dev, REG_STEPDELAY(total_steps + 1),
                        STEPCONFIG_OPENDLY);
 
-       config |= STEPCONFIG_INP_AN3 | STEPCONFIG_FIFO1;
+       config |= STEPCONFIG_INP(ts_dev->inp_yn) | STEPCONFIG_FIFO1;
        titsc_writel(ts_dev, REG_STEPCONFIG(total_steps + 2), config);
        titsc_writel(ts_dev, REG_STEPDELAY(total_steps + 2),
                        STEPCONFIG_OPENDLY);
@@ -292,6 +355,8 @@ static int titsc_probe(struct platform_device *pdev)
        ts_dev->wires = pdata->tsc_init->wires;
        ts_dev->x_plate_resistance = pdata->tsc_init->x_plate_resistance;
        ts_dev->steps_to_configure = pdata->tsc_init->steps_to_configure;
+       memcpy(ts_dev->config_inp, pdata->tsc_init->wire_config,
+                       sizeof(pdata->tsc_init->wire_config));
 
        err = request_irq(ts_dev->irq, titsc_irq,
                          0, pdev->dev.driver->name, ts_dev);
@@ -301,6 +366,11 @@ static int titsc_probe(struct platform_device *pdev)
        }
 
        titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
+       err = titsc_config_wires(ts_dev);
+       if (err) {
+               dev_err(&pdev->dev, "wrong i/p wire configuration\n");
+               goto err_free_irq;
+       }
        titsc_step_config(ts_dev);
        titsc_writel(ts_dev, REG_FIFO0THR, ts_dev->steps_to_configure);
 

diff --git a/include/linux/input/ti_am335x_tsc.h b/include/linux/input/ti_am335x_tsc.h
index 49269a2aa329ee84f99e3807cc0b782a53c9f85f..6a66b4d1ac2c34cfaeaea4d0b53f1275f7651b39 100644 (file)
--- a/include/linux/input/ti_am335x_tsc.h
+++ b/include/linux/input/ti_am335x_tsc.h
@@ -12,12 +12,24 @@
  *                     A step configured to read a single
  *                     co-ordinate value, can be applied
  *                     more number of times for better results.
+ * @wire_config:       Different EVM's could have a different order
+ *                     for connecting wires on touchscreen.
+ *                     We need to provide an 8 bit number where in
+ *                     the 1st four bits represent the analog lines
+ *                     and the next 4 bits represent positive/
+ *                     negative terminal on that input line.
+ *                     Notations to represent the input lines and
+ *                     terminals resoectively is as follows:
+ *                     AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7.
+ *                     XP  = 0, XN = 1, YP = 2, YN = 3.
+ *
  */
 
 struct tsc_data {
        int wires;
        int x_plate_resistance;
        int steps_to_configure;
+       int wire_config[10];
 };
 
 #endif

diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
index 4258627d076a1b6e432df7c951f8df1f2134797e..e36ae418491708133871da434606c6b3ebaa1a71 100644 (file)
--- a/include/linux/mfd/ti_am335x_tscadc.h
+++ b/include/linux/mfd/ti_am335x_tscadc.h
@@ -71,8 +71,6 @@
 #define STEPCONFIG_INM_ADCREFM STEPCONFIG_INM(8)
 #define STEPCONFIG_INP_MASK    (0xF << 19)
 #define STEPCONFIG_INP(val)    ((val) << 19)
-#define STEPCONFIG_INP_AN2     STEPCONFIG_INP(2)
-#define STEPCONFIG_INP_AN3     STEPCONFIG_INP(3)
 #define STEPCONFIG_INP_AN4     STEPCONFIG_INP(4)
 #define STEPCONFIG_INP_ADCREFM STEPCONFIG_INP(8)
 #define STEPCONFIG_FIFO1       BIT(26)
@@ -94,7 +92,6 @@
 #define STEPCHARGE_INM_AN1     STEPCHARGE_INM(1)
 #define STEPCHARGE_INP_MASK    (0xF << 19)
 #define STEPCHARGE_INP(val)    ((val) << 19)
-#define STEPCHARGE_INP_AN1     STEPCHARGE_INP(1)
 #define STEPCHARGE_RFM_MASK    (3 << 23)
 #define STEPCHARGE_RFM(val)    ((val) << 23)
 #define STEPCHARGE_RFM_XNUR    STEPCHARGE_RFM(1)