gpio: stmpe: Fix edge and rising/falling edge detection

By cross-checking STMPE 610/801/811/1601/2401/2403 datasheets,
it appears that edge detection and rising/falling edge detection
is not supported by all STMPE variant:

           GPIO              GPIO
      Edge detection     rising/falling
                         edge detection
 610 |      X        |         X       |
 801 |               |                 |
 811 |      X        |         X       |
1600 |               |                 |
1601 |      X        |         X       |
1801 |               |         X       |
2401 |      X        |         X       |
2403 |      X        |         X       |

Rework stmpe_dbg_show_one() and stmpe_gpio_irq to correctly
take these cases into account.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
index f675132..fdac5d9 100644 (file)
--- a/drivers/gpio/gpio-stmpe.c
+++ b/drivers/gpio/gpio-stmpe.c
@@ -247,39 +247,74 @@ static void stmpe_dbg_show_one(struct seq_file *s,
                           gpio, label ?: "(none)",
                           val ? "hi" : "lo");
        } else {
-               u8 edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_MSB] + num_banks - 1 - (offset / 8);
-               u8 rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB] - (offset / 8);
-               u8 fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB] - (offset / 8);
-               u8 irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB] - (offset / 8);
-               bool edge_det;
-               bool rise;
-               bool fall;
+               u8 edge_det_reg;
+               u8 rise_reg;
+               u8 fall_reg;
+               u8 irqen_reg;
+
+               char *edge_det_values[] = {"edge-inactive",
+                                          "edge-asserted",
+                                          "not-supported"};
+               char *rise_values[] = {"no-rising-edge-detection",
+                                      "rising-edge-detection",
+                                      "not-supported"};
+               char *fall_values[] = {"no-falling-edge-detection",
+                                      "falling-edge-detection",
+                                      "not-supported"};
+               #define NOT_SUPPORTED_IDX 2
+               u8 edge_det = NOT_SUPPORTED_IDX;
+               u8 rise = NOT_SUPPORTED_IDX;
+               u8 fall = NOT_SUPPORTED_IDX;
                bool irqen;
 
-               ret = stmpe_reg_read(stmpe, edge_det_reg);
-               if (ret < 0)
-                       return;
-               edge_det = !!(ret & mask);
-               ret = stmpe_reg_read(stmpe, rise_reg);
-               if (ret < 0)
+               switch (stmpe->partnum) {
+               case STMPE610:
+               case STMPE811:
+               case STMPE1601:
+               case STMPE2401:
+               case STMPE2403:
+                       edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_MSB] +
+                                      num_banks - 1 - (offset / 8);
+                       ret = stmpe_reg_read(stmpe, edge_det_reg);
+                       if (ret < 0)
+                               return;
+                       edge_det = !!(ret & mask);
+
+               case STMPE1801:
+                       rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB] -
+                                  (offset / 8);
+                       fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB] -
+                                  (offset / 8);
+                       ret = stmpe_reg_read(stmpe, rise_reg);
+                       if (ret < 0)
+                               return;
+                       rise = !!(ret & mask);
+                       ret = stmpe_reg_read(stmpe, fall_reg);
+                       if (ret < 0)
+                               return;
+                       fall = !!(ret & mask);
+
+               case STMPE801:
+                       irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB] -
+                                   (offset / 8);
+                       break;
+
+               default:
                        return;
-               rise = !!(ret & mask);
-               ret = stmpe_reg_read(stmpe, fall_reg);
-               if (ret < 0)
-                       return;
-               fall = !!(ret & mask);
+               }
+
                ret = stmpe_reg_read(stmpe, irqen_reg);
                if (ret < 0)
                        return;
                irqen = !!(ret & mask);
 
-               seq_printf(s, " gpio-%-3d (%-20.20s) in  %s %s %s%s%s",
+               seq_printf(s, " gpio-%-3d (%-20.20s) in  %s %13s %13s %25s %25s",
                           gpio, label ?: "(none)",
                           val ? "hi" : "lo",
-                          edge_det ? "edge-asserted" : "edge-inactive",
-                          irqen ? "IRQ-enabled" : "",
-                          rise ? " rising-edge-detection" : "",
-                          fall ? " falling-edge-detection" : "");
+                          edge_det_values[edge_det],
+                          irqen ? "IRQ-enabled" : "IRQ-disabled",
+                          rise_values[rise],
+                          fall_values[fall]);
        }
 }
 
@@ -338,8 +373,8 @@ static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
 
                stmpe_reg_write(stmpe, statmsbreg + i, status[i]);
 
-               /* Edge detect register is not present on 801 */
-               if (stmpe->partnum != STMPE801)
+               /* Edge detect register is not present on 801 and 1801 */
+               if (stmpe->partnum != STMPE801 || stmpe->partnum != STMPE1801)
                        stmpe_reg_write(stmpe, stmpe->regs[STMPE_IDX_GPEDR_MSB]
                                        + i, status[i]);
        }