davinci: dm365 evm cpld support: leds, card detect, other setup

Add basic support for the CPLD on the DM365 EVM board:

 - Read SW5 to set up NAND and keypad vs (someday) OneNAND
 - Export MMC/SD card detect and writeprotect signals
 - LED support (same layout as on DM355 EVM)
 - Static config for video input:
     * external HD imager precludes MMC1, Ethernet, audio
     * else either tvp5146 (SD/default) or tvp7002 (HD)

The video input could actually be switched around dynamically;
change that if/when that's needed (and after those other video
inputs have driver support).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-davinci/board-dm365-evm.c

@@ -20,6 +20,7 @@
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/i2c/at24.h>
+#include <linux/leds.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
 #include <linux/mtd/nand.h>
@@ -33,18 +34,71 @@
 #include <mach/psc.h>
 #include <mach/common.h>
 #include <mach/i2c.h>
-#include <linux/i2c.h>
 #include <mach/serial.h>
 #include <mach/common.h>
 #include <mach/mmc.h>
 #include <mach/nand.h>
 
+
+static inline int have_imager(void)
+{
+	/* REVISIT when it's supported, trigger via Kconfig */
+	return 0;
+}
+
+static inline int have_tvp7002(void)
+{
+	/* REVISIT when it's supported, trigger via Kconfig */
+	return 0;
+}
+
+
 #define DM365_ASYNC_EMIF_CONTROL_BASE	0x01d10000
 #define DM365_ASYNC_EMIF_DATA_CE0_BASE	0x02000000
+#define DM365_ASYNC_EMIF_DATA_CE1_BASE	0x04000000
 
 #define DM365_EVM_PHY_MASK		(0x2)
 #define DM365_EVM_MDIO_FREQUENCY	(2200000) /* PHY bus frequency */
 
+/*
+ * A MAX-II CPLD is used for various board control functions.
+ */
+#define CPLD_OFFSET(a13a8,a2a1)		(((a13a8) << 10) + ((a2a1) << 3))
+
+#define CPLD_VERSION	CPLD_OFFSET(0,0)	/* r/o */
+#define CPLD_TEST	CPLD_OFFSET(0,1)
+#define CPLD_LEDS	CPLD_OFFSET(0,2)
+#define CPLD_MUX	CPLD_OFFSET(0,3)
+#define CPLD_SWITCH	CPLD_OFFSET(1,0)	/* r/o */
+#define CPLD_POWER	CPLD_OFFSET(1,1)
+#define CPLD_VIDEO	CPLD_OFFSET(1,2)
+#define CPLD_CARDSTAT	CPLD_OFFSET(1,3)	/* r/o */
+
+#define CPLD_DILC_OUT	CPLD_OFFSET(2,0)
+#define CPLD_DILC_IN	CPLD_OFFSET(2,1)	/* r/o */
+
+#define CPLD_IMG_DIR0	CPLD_OFFSET(2,2)
+#define CPLD_IMG_MUX0	CPLD_OFFSET(2,3)
+#define CPLD_IMG_MUX1	CPLD_OFFSET(3,0)
+#define CPLD_IMG_DIR1	CPLD_OFFSET(3,1)
+#define CPLD_IMG_MUX2	CPLD_OFFSET(3,2)
+#define CPLD_IMG_MUX3	CPLD_OFFSET(3,3)
+#define CPLD_IMG_DIR2	CPLD_OFFSET(4,0)
+#define CPLD_IMG_MUX4	CPLD_OFFSET(4,1)
+#define CPLD_IMG_MUX5	CPLD_OFFSET(4,2)
+
+#define CPLD_RESETS	CPLD_OFFSET(4,3)
+
+#define CPLD_CCD_DIR1	CPLD_OFFSET(0x3e,0)
+#define CPLD_CCD_IO1	CPLD_OFFSET(0x3e,1)
+#define CPLD_CCD_DIR2	CPLD_OFFSET(0x3e,2)
+#define CPLD_CCD_IO2	CPLD_OFFSET(0x3e,3)
+#define CPLD_CCD_DIR3	CPLD_OFFSET(0x3f,0)
+#define CPLD_CCD_IO3	CPLD_OFFSET(0x3f,1)
+
+static void __iomem *cpld;
+
+
 /* NOTE:  this is geared for the standard config, with a socketed
  * 2 GByte Micron NAND (MT29F16G08FAA) using 128KB sectors.  If you
  * swap chips with a different block size, partitioning will
@@ -135,7 +189,27 @@ static struct davinci_i2c_platform_data i2c_pdata = {
 	.bus_delay	= 0	/* usec */,
 };
 
+static int cpld_mmc_get_cd(int module)
+{
+	if (!cpld)
+		return -ENXIO;
+
+	/* low == card present */
+	return !(__raw_readb(cpld + CPLD_CARDSTAT) & BIT(module ? 4 : 0));
+}
+
+static int cpld_mmc_get_ro(int module)
+{
+	if (!cpld)
+		return -ENXIO;
+
+	/* high == card's write protect switch active */
+	return !!(__raw_readb(cpld + CPLD_CARDSTAT) & BIT(module ? 5 : 1));
+}
+
 static struct davinci_mmc_config dm365evm_mmc_config = {
+	.get_cd		= cpld_mmc_get_cd,
+	.get_ro		= cpld_mmc_get_ro,
 	.wires		= 4,
 	.max_freq	= 50000000,
 	.caps		= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED,
@@ -199,10 +273,185 @@ static void __init evm_init_i2c(void)
 	i2c_register_board_info(1, i2c_info, ARRAY_SIZE(i2c_info));
 }
 
-static struct platform_device *dm365_evm_devices[] __initdata = {
+static struct platform_device *dm365_evm_nand_devices[] __initdata = {
 	&davinci_nand_device,
 };
 
+static inline int have_leds(void)
+{
+#ifdef CONFIG_LEDS_CLASS
+	return 1;
+#else
+	return 0;
+#endif
+}
+
+struct cpld_led {
+	struct led_classdev	cdev;
+	u8			mask;
+};
+
+static const struct {
+	const char *name;
+	const char *trigger;
+} cpld_leds[] = {
+	{ "dm365evm::ds2", },
+	{ "dm365evm::ds3", },
+	{ "dm365evm::ds4", },
+	{ "dm365evm::ds5", },
+	{ "dm365evm::ds6", "nand-disk", },
+	{ "dm365evm::ds7", "mmc1", },
+	{ "dm365evm::ds8", "mmc0", },
+	{ "dm365evm::ds9", "heartbeat", },
+};
+
+static void cpld_led_set(struct led_classdev *cdev, enum led_brightness b)
+{
+	struct cpld_led *led = container_of(cdev, struct cpld_led, cdev);
+	u8 reg = __raw_readb(cpld + CPLD_LEDS);
+
+	if (b != LED_OFF)
+		reg &= ~led->mask;
+	else
+		reg |= led->mask;
+	__raw_writeb(reg, cpld + CPLD_LEDS);
+}
+
+static enum led_brightness cpld_led_get(struct led_classdev *cdev)
+{
+	struct cpld_led *led = container_of(cdev, struct cpld_led, cdev);
+	u8 reg = __raw_readb(cpld + CPLD_LEDS);
+
+	return (reg & led->mask) ? LED_OFF : LED_FULL;
+}
+
+static int __init cpld_leds_init(void)
+{
+	int	i;
+
+	if (!have_leds() ||  !cpld)
+		return 0;
+
+	/* setup LEDs */
+	__raw_writeb(0xff, cpld + CPLD_LEDS);
+	for (i = 0; i < ARRAY_SIZE(cpld_leds); i++) {
+		struct cpld_led *led;
+
+		led = kzalloc(sizeof(*led), GFP_KERNEL);
+		if (!led)
+			break;
+
+		led->cdev.name = cpld_leds[i].name;
+		led->cdev.brightness_set = cpld_led_set;
+		led->cdev.brightness_get = cpld_led_get;
+		led->cdev.default_trigger = cpld_leds[i].trigger;
+		led->mask = BIT(i);
+
+		if (led_classdev_register(NULL, &led->cdev) < 0) {
+			kfree(led);
+			break;
+		}
+	}
+
+	return 0;
+}
+/* run after subsys_initcall() for LEDs */
+fs_initcall(cpld_leds_init);
+
+
+static void __init evm_init_cpld(void)
+{
+	u8 mux, resets;
+	const char *label;
+	struct clk *aemif_clk;
+
+	/* Make sure we can configure the CPLD through CS1.  Then
+	 * leave it on for later access to MMC and LED registers.
+	 */
+	aemif_clk = clk_get(NULL, "aemif");
+	if (IS_ERR(aemif_clk))
+		return;
+	clk_enable(aemif_clk);
+
+	if (request_mem_region(DM365_ASYNC_EMIF_DATA_CE1_BASE, SECTION_SIZE,
+			"cpld") == NULL)
+		goto fail;
+	cpld = ioremap(DM365_ASYNC_EMIF_DATA_CE1_BASE, SECTION_SIZE);
+	if (!cpld) {
+		release_mem_region(DM365_ASYNC_EMIF_DATA_CE1_BASE,
+				SECTION_SIZE);
+fail:
+		pr_err("ERROR: can't map CPLD\n");
+		clk_disable(aemif_clk);
+		return;
+	}
+
+	/* External muxing for some signals */
+	mux = 0;
+
+	/* Read SW5 to set up NAND + keypad _or_ OneNAND (sync read).
+	 * NOTE:  SW4 bus width setting must match!
+	 */
+	if ((__raw_readb(cpld + CPLD_SWITCH) & BIT(5)) == 0) {
+		/* external keypad mux */
+		mux |= BIT(7);
+
+		platform_add_devices(dm365_evm_nand_devices,
+				ARRAY_SIZE(dm365_evm_nand_devices));
+	} else {
+		/* no OneNAND support yet */
+	}
+
+	/* Leave external chips in reset when unused. */
+	resets = BIT(3) | BIT(2) | BIT(1) | BIT(0);
+
+	/* Static video input config with SN74CBT16214 1-of-3 mux:
+	 *  - port b1 == tvp7002 (mux lowbits == 1 or 6)
+	 *  - port b2 == imager (mux lowbits == 2 or 7)
+	 *  - port b3 == tvp5146 (mux lowbits == 5)
+	 *
+	 * Runtime switching could work too, with limitations.
+	 */
+	if (have_imager()) {
+		label = "HD imager";
+		mux |= 1;
+
+		/* externally mux MMC1/ENET/AIC33 to imager */
+		mux |= BIT(6) | BIT(5) | BIT(3);
+	} else {
+		struct davinci_soc_info *soc_info = &davinci_soc_info;
+
+		/* we can use MMC1 ... */
+		dm365evm_mmc_configure();
+		davinci_setup_mmc(1, &dm365evm_mmc_config);
+
+		/* ... and ENET ... */
+		dm365evm_emac_configure();
+		soc_info->emac_pdata->phy_mask = DM365_EVM_PHY_MASK;
+		soc_info->emac_pdata->mdio_max_freq = DM365_EVM_MDIO_FREQUENCY;
+		resets &= ~BIT(3);
+
+		/* ... and AIC33 */
+		resets &= ~BIT(1);
+
+		if (have_tvp7002()) {
+			mux |= 2;
+			resets &= ~BIT(2);
+			label = "tvp7002 HD";
+		} else {
+			/* default to tvp5146 */
+			mux |= 5;
+			resets &= ~BIT(0);
+			label = "tvp5146 SD";
+		}
+	}
+	__raw_writeb(mux, cpld + CPLD_MUX);
+	__raw_writeb(resets, cpld + CPLD_RESETS);
+	pr_info("EVM: %s video input\n", label);
+
+	/* REVISIT export switches: NTSC/PAL (SW5.6), EXTRA1 (SW5.2), etc */
+}
+
 static struct davinci_uart_config uart_config __initdata = {
 	.enabled_uarts = (1 << 0),
 };
@@ -214,11 +463,6 @@ static void __init dm365_evm_map_io(void)
 
 static __init void dm365_evm_init(void)
 {
-	struct davinci_soc_info *soc_info = &davinci_soc_info;
-
-	platform_add_devices(dm365_evm_devices,
-				ARRAY_SIZE(dm365_evm_devices));
-
 	evm_init_i2c();
 	davinci_serial_init(&uart_config);
 
@@ -226,10 +470,9 @@ static __init void dm365_evm_init(void)
 	dm365evm_mmc_configure();
 
 	davinci_setup_mmc(0, &dm365evm_mmc_config);
-	davinci_setup_mmc(1, &dm365evm_mmc_config);
 
-	soc_info->emac_pdata->phy_mask = DM365_EVM_PHY_MASK;
-	soc_info->emac_pdata->mdio_max_freq = DM365_EVM_MDIO_FREQUENCY;
+	/* maybe setup mmc1/etc ... _after_ mmc0 */
+	evm_init_cpld();
 }
 
 static __init void dm365_evm_irq_init(void)