ENGR00170323-mx6q:sabreauto:fix_flexcan_IO_expander_and_pad_settings

Fix CAN1 STBY, EN and STEER pins to be managed through
the IO expander(2) using GPIO's 3,5 and 6. Routes CAN2
TX pin correctly.STEER pin is managed dynamically when
either of the CAN interfaces is UP and/or DOWN.
CAN definitions removed for code clarification.

Signed-off-by: Oscar Luna <r01160@freescale.com>

1 files changed, 45 insertions, 37 deletions

diff --git a/arch/arm/mach-mx6/board-mx6q_sabreauto.c b/arch/arm/mach-mx6/board-mx6q_sabreauto.c
index f5b2f6bca77..c82bfb8991f 100644
--- a/arch/arm/mach-mx6/board-mx6q_sabreauto.c
+++ b/arch/arm/mach-mx6/board-mx6q_sabreauto.c
@@ -102,11 +102,14 @@
 #define MX6Q_SABREAUTO_IO_EXP_GPIO3(x) \
 		(MX6Q_SABREAUTO_MAX7310_3_BASE_ADDR + (x))
 
-#define MX6Q_SABREAUTO_CAN1_STBY       IMX_GPIO_NR(7, 12)
-#define MX6Q_SABREAUTO_CAN1_EN         IMX_GPIO_NR(7, 13)
-#define MX6Q_SABREAUTO_CAN2_STBY       MX6Q_SABREAUTO_IO_EXP_GPIO2(1)
+/*  CAN2 STBY and EN lines are the same as the CAN1. These lines are not
+ *  independent.
+ */
+#define MX6Q_SABREAUTO_CAN1_STEER       MX6Q_SABREAUTO_IO_EXP_GPIO2(3)
+#define MX6Q_SABREAUTO_CAN_STBY         MX6Q_SABREAUTO_IO_EXP_GPIO2(5)
+#define MX6Q_SABREAUTO_CAN_EN           MX6Q_SABREAUTO_IO_EXP_GPIO2(6)
+
 #define MX6Q_SABREAUTO_VIDEOIN_PWR     MX6Q_SABREAUTO_IO_EXP_GPIO2(2)
-#define MX6Q_SABREAUTO_CAN2_EN         IMX_GPIO_NR(5, 24)
 #define MX6Q_SABREAUTO_I2C_EXP_RST     IMX_GPIO_NR(1, 15)
 #define MX6Q_SABREAUTO_ESAI_INT        IMX_GPIO_NR(1, 10)
 #define MX6Q_SABREAUTO_PER_RST         MX6Q_SABREAUTO_IO_EXP_GPIO1(3)
@@ -325,15 +328,12 @@ static iomux_v3_cfg_t mx6q_sabreauto_i2c3_pads[] = {
 
 static iomux_v3_cfg_t mx6q_sabreauto_can_pads[] = {
 	/* CAN1 */
-	MX6Q_PAD_GPIO_7__CAN1_TXCAN,
+	MX6Q_PAD_KEY_COL2__CAN1_TXCAN,
 	MX6Q_PAD_KEY_ROW2__CAN1_RXCAN,
-	MX6Q_PAD_GPIO_17__GPIO_7_12,	/* CAN1 STBY */
-	MX6Q_PAD_GPIO_18__GPIO_7_13,	/* CAN1 EN */
 
 	/* CAN2 */
 	MX6Q_PAD_KEY_COL4__CAN2_TXCAN,
 	MX6Q_PAD_KEY_ROW4__CAN2_RXCAN,
-	MX6Q_PAD_CSI0_DAT6__GPIO_5_24,	/* CAN2 EN */
 };
 
 static iomux_v3_cfg_t mx6q_sabreauto_esai_record_pads[] = {
@@ -1033,33 +1033,47 @@ static struct platform_pwm_backlight_data mx6_sabreauto_pwm_backlight_data = {
 	.dft_brightness = 128,
 	.pwm_period_ns = 50000,
 };
+static int flexcan0_en;
+static int flexcan1_en;
 
-static struct gpio mx6q_flexcan_gpios[] = {
-	{ MX6Q_SABREAUTO_CAN1_EN, GPIOF_OUT_INIT_LOW, "flexcan1-en" },
-	{ MX6Q_SABREAUTO_CAN1_STBY, GPIOF_OUT_INIT_LOW, "flexcan1-stby" },
-	{ MX6Q_SABREAUTO_CAN2_EN, GPIOF_OUT_INIT_LOW, "flexcan2-en" },
-};
-
+static void mx6q_flexcan_switch(void)
+{
+  if (flexcan0_en || flexcan1_en) {
+	gpio_set_value_cansleep(MX6Q_SABREAUTO_CAN_EN, 1);
+	gpio_set_value_cansleep(MX6Q_SABREAUTO_CAN_STBY, 1);
+	/* Enable STEER pin if CAN1 interface is required.
+	 * STEER pin is used to switch between ENET_MDC
+	 * and CAN1_TX functionality. By default ENET_MDC
+	 * is active after reset.
+	 */
+	if (flexcan0_en)
+		gpio_set_value_cansleep(MX6Q_SABREAUTO_CAN1_STEER, 1);
+
+  } else {
+    /* avoid to disable CAN xcvr if any of the CAN interfaces
+    * are down. XCRV will be disabled only if both CAN2
+    * interfaces are DOWN.
+    */
+    if (!flexcan0_en && !flexcan1_en) {
+	gpio_set_value_cansleep(MX6Q_SABREAUTO_CAN_EN, 0);
+	gpio_set_value_cansleep(MX6Q_SABREAUTO_CAN_STBY, 0);
+    }
+    /* turn down STEER pin only if CAN1 is DOWN */
+    if (!flexcan0_en)
+	gpio_set_value_cansleep(MX6Q_SABREAUTO_CAN1_STEER, 0);
+
+  }
+}
 static void mx6q_flexcan0_switch(int enable)
 {
-	if (enable) {
-		gpio_set_value(MX6Q_SABREAUTO_CAN1_EN, 1);
-		gpio_set_value(MX6Q_SABREAUTO_CAN1_STBY, 1);
-	} else {
-		gpio_set_value(MX6Q_SABREAUTO_CAN1_EN, 0);
-		gpio_set_value(MX6Q_SABREAUTO_CAN1_STBY, 0);
-	}
+    flexcan0_en = enable;
+    mx6q_flexcan_switch();
 }
 
 static void mx6q_flexcan1_switch(int enable)
 {
-	if (enable) {
-		gpio_set_value(MX6Q_SABREAUTO_CAN2_EN, 1);
-		gpio_set_value(MX6Q_SABREAUTO_CAN2_STBY, 1);
-	} else {
-		gpio_set_value(MX6Q_SABREAUTO_CAN2_EN, 0);
-		gpio_set_value(MX6Q_SABREAUTO_CAN2_STBY, 0);
-	}
+    flexcan1_en = enable;
+    mx6q_flexcan_switch();
 }
 
 static const struct flexcan_platform_data
@@ -1353,7 +1367,7 @@ static struct mxc_spdif_platform_data mxc_spdif_data = {
 static void __init mx6_board_init(void)
 {
 	int i;
-	int ret;
+    int ret;
 
 	mxc_iomux_v3_setup_multiple_pads(mx6q_sabreauto_pads,
 					ARRAY_SIZE(mx6q_sabreauto_pads));
@@ -1478,14 +1492,8 @@ static void __init mx6_board_init(void)
 	imx6q_add_spdif_dai();
 	imx6q_add_spdif_audio_device();
 
-	ret = gpio_request_array(mx6q_flexcan_gpios,
-				ARRAY_SIZE(mx6q_flexcan_gpios));
-	if (ret) {
-		pr_err("failed to request flexcan-gpios: %d\n", ret);
-	} else {
-		imx6q_add_flexcan0(&mx6q_sabreauto_flexcan_pdata[0]);
-		imx6q_add_flexcan1(&mx6q_sabreauto_flexcan_pdata[1]);
-	}
+	imx6q_add_flexcan0(&mx6q_sabreauto_flexcan_pdata[0]);
+	imx6q_add_flexcan1(&mx6q_sabreauto_flexcan_pdata[1]);
 
 	imx6q_add_hdmi_soc();
 	imx6q_add_hdmi_soc_dai();