[U-Boot] [PATCH] i.MX6: mx6qsabrelite: Add keypress support

[Eric Nelson <eric.nelson@boundarydevices.com>]

This patch adds support for the GPIO keyboard used on MX6Q SabreLite.

This is generally used for invoking Android "recovery mode" in
response to a long press of volume key down during boot.

This can be tested by a boot script like so:
    if keypress voldown && sleep 1 && keypress voldown ; then
          echo "do recovery thing" ;
    fi

Key values can be seen by issuing keypress with no arguments:

	MX6QSABRELITE U-Boot > keypress
	keys: !menu	!back	!search	!home	!volup	!voldown
---
 board/freescale/mx6qsabrelite/mx6qsabrelite.c |   76 +++++++++++++++++++++++++
 1 files changed, 76 insertions(+), 0 deletions(-)

diff --git a/board/freescale/mx6qsabrelite/mx6qsabrelite.c b/board/freescale/mx6qsabrelite/mx6qsabrelite.c
index e0ba6a4..0d45615 100644
--- a/board/freescale/mx6qsabrelite/mx6qsabrelite.c
+++ b/board/freescale/mx6qsabrelite/mx6qsabrelite.c
@@ -50,6 +50,10 @@ DECLARE_GLOBAL_DATA_PTR;
 	PAD_CTL_PUS_100K_DOWN | PAD_CTL_SPEED_MED |		\
 	PAD_CTL_DSE_40ohm     | PAD_CTL_SRE_FAST)
 
+#define BUTTON_PAD_CTRL (PAD_CTL_PKE | PAD_CTL_PUE |		\
+	PAD_CTL_PUS_100K_UP | PAD_CTL_SPEED_MED   |		\
+	PAD_CTL_DSE_40ohm   | PAD_CTL_HYS)
+
 int dram_init(void)
 {
        gd->ram_size = get_ram_size((void *)PHYS_SDRAM, PHYS_SDRAM_SIZE);
@@ -122,6 +126,15 @@ iomux_v3_cfg_t enet_pads2[] = {
 	MX6Q_PAD_RGMII_RX_CTL__RGMII_RX_CTL	| MUX_PAD_CTRL(ENET_PAD_CTRL),
 };
 
+static iomux_v3_cfg_t const button_pads[] = {
+	MX6Q_PAD_NANDF_D1__GPIO_2_1	| MUX_PAD_CTRL(BUTTON_PAD_CTRL), /* J14 - Menu Button */
+	MX6Q_PAD_NANDF_D2__GPIO_2_2	| MUX_PAD_CTRL(BUTTON_PAD_CTRL), /* J14 - Back Button */
+	MX6Q_PAD_NANDF_D3__GPIO_2_3	| MUX_PAD_CTRL(BUTTON_PAD_CTRL), /* J14 - Search Button */
+	MX6Q_PAD_NANDF_D4__GPIO_2_4	| MUX_PAD_CTRL(BUTTON_PAD_CTRL), /* J14 - Home Button */
+	MX6Q_PAD_GPIO_19__GPIO_4_5	| MUX_PAD_CTRL(BUTTON_PAD_CTRL), /* J14 - Volume Down */
+	MX6Q_PAD_GPIO_18__GPIO_7_13	| MUX_PAD_CTRL(BUTTON_PAD_CTRL), /* J14 - Volume Up */
+};
+
 static void setup_iomux_enet(void)
 {
 	gpio_direction_output(87, 0);  /* GPIO 3-23 */
@@ -323,10 +336,18 @@ int setup_sata(void)
 }
 #endif
 
+static void setup_buttons(void)
+{
+	imx_iomux_v3_setup_multiple_pads(button_pads,
+					 ARRAY_SIZE(button_pads));
+}
+
 int board_early_init_f(void)
 {
        setup_iomux_uart();
 
+       setup_buttons();
+
 #ifdef CONFIG_CMD_SATA
 	setup_sata();
 #endif
@@ -350,3 +371,58 @@ int checkboard(void)
 
        return 0;
 }
+
+struct button_key {
+	char const	*name;
+	unsigned	gpnum;
+};
+
+static struct button_key const buttons[] = {
+	{"menu",	GPIO_NUMBER(2, 1)},
+	{"back",	GPIO_NUMBER(2, 2)},
+	{"search",	GPIO_NUMBER(2, 3)},
+	{"home",	GPIO_NUMBER(2, 4)},
+	{"voldown",	GPIO_NUMBER(4, 5)},
+	{"volup",	GPIO_NUMBER(7, 13)},
+};
+
+static int keypress(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	if (1 < argc) {
+		int arg;
+		int pressed = 1 ;
+		for (arg=1; arg<argc; arg++) {
+			char const *keyname=argv[arg];
+			int i;
+			for (i=0; pressed && (i < ARRAY_SIZE(buttons)); i++) {
+				if (0 == strcmp(buttons[i].name,keyname)) {
+					pressed = pressed && (0 == gpio_get_value(buttons[i].gpnum));
+					break;
+				}
+			}
+			if (ARRAY_SIZE(buttons) == i) {
+				printf ("unrecognized key %s\n", keyname);
+				pressed = 0;
+				break;
+			}
+		}
+		return (0 == pressed);
+	} else {
+		int i;
+		printf ("keys: ");
+		for (i=0; i<ARRAY_SIZE(buttons); i++) {
+			if (0 != gpio_get_value(buttons[i].gpnum))
+				printf("!");
+			printf("%s\t",buttons[i].name);
+		}
+		printf("\n");
+		return 0 ;
+	}
+}
+
+U_BOOT_CMD(
+	keypress, CONFIG_SYS_MAXARGS, 1, keypress,
+	"Display or test keypresses",
+	"    keypress		- show key(s) pressed\n"
+	"    keypress name	- test key name (return 0 if pressed)\n"
+);
-- 
1.7.9