[PATCH] ARM: davinci: usb: provide minimal support for da850.

[Paul Chavent]

As for the da830 and hawk boards, the da850 can provide minimalist usb
1.1 implementation. Moreover, this patch has only been tested with the
OHCI (on an OMAP L138 EVM / DA850 board), not with the Inventra HC
(that seems broken for the DA8XX).

This patch is inspired by the hawk board implementation.

Signed-off-by: Paul Chavent <paul.chavent at onera.fr>
---
 arch/arm/mach-davinci/board-da850-evm.c | 153 ++++++++++++++++++++++++++++++++
 1 file changed, 153 insertions(+)

diff --git a/arch/arm/mach-davinci/board-da850-evm.c b/arch/arm/mach-davinci/board-da850-evm.c
index dd1fb24..f0bee9d 100644
--- a/arch/arm/mach-davinci/board-da850-evm.c
+++ b/arch/arm/mach-davinci/board-da850-evm.c
@@ -62,6 +62,9 @@
 
 #define DA850_MII_MDIO_CLKEN_PIN	GPIO_TO_PIN(2, 6)
 
+#define DA850_USB1_VBUS_PIN		GPIO_TO_PIN(2, 4)
+#define DA850_USB1_OC_PIN		GPIO_TO_PIN(6, 13)
+
 static struct mtd_partition da850evm_spiflash_part[] = {
 	[0] = {
 		.name = "UBL",
@@ -1431,6 +1434,155 @@ static __init int da850_wl12xx_init(void)
 
 #endif /* CONFIG_DA850_WL12XX */
 
+#ifdef CONFIG_USB
+
+static irqreturn_t da850_usb_ocic_irq(int irq, void *dev_id);
+static da8xx_ocic_handler_t da850_usb_ocic_handler;
+
+static const short da850_usb11_pins[] = {
+	DA850_GPIO2_4, DA850_GPIO6_13,
+	-1
+};
+
+static int da850_usb_set_power(unsigned port, int on)
+{
+	gpio_set_value(DA850_USB1_VBUS_PIN, on);
+	return 0;
+}
+
+static int da850_usb_get_power(unsigned port)
+{
+	return gpio_get_value(DA850_USB1_VBUS_PIN);
+}
+
+static int da850_usb_get_oci(unsigned port)
+{
+	return !gpio_get_value(DA850_USB1_OC_PIN);
+}
+
+static int da850_usb_ocic_notify(da8xx_ocic_handler_t handler)
+{
+	int irq         = gpio_to_irq(DA850_USB1_OC_PIN);
+	int error       = 0;
+
+	if (handler != NULL) {
+		da850_usb_ocic_handler = handler;
+
+		error = request_irq(irq, da850_usb_ocic_irq,
+					IRQF_DISABLED | IRQF_TRIGGER_RISING |
+					IRQF_TRIGGER_FALLING,
+					"OHCI over-current indicator", NULL);
+		if (error)
+			pr_err("%s: could not request IRQ to watch "
+				"over-current indicator changes\n", __func__);
+	} else {
+		free_irq(irq, NULL);
+	}
+	return error;
+}
+
+static struct da8xx_ohci_root_hub da850_usb11_pdata = {
+	.set_power      = da850_usb_set_power,
+	.get_power      = da850_usb_get_power,
+	.get_oci        = da850_usb_get_oci,
+	.ocic_notify    = da850_usb_ocic_notify,
+	/* TPS2087 switch @ 5V */
+	.potpgt         = (3 + 1) / 2,  /* 3 ms max */
+};
+
+static irqreturn_t da850_usb_ocic_irq(int irq, void *dev_id)
+{
+	da850_usb_ocic_handler(&da850_usb11_pdata, 1);
+	return IRQ_HANDLED;
+}
+
+static __init void da850_usb_init(void)
+{
+	void __iomem *cfg_chip2_base;
+	int ret;
+	u32 val;
+
+	/*
+	 * Set up USB clock/mode in the CFGCHIP2 register.
+	 */
+
+	cfg_chip2_base = DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP2_REG);
+
+	val = __raw_readl(cfg_chip2_base);
+
+	/* USB2.0 PHY reference clock is 24 MHz */
+	val &= ~CFGCHIP2_REFFREQ;
+	val |=  CFGCHIP2_REFFREQ_24MHZ;
+
+	/*
+	 * Select internal reference clock for USB 2.0 PHY
+	 * and use it as a clock source for USB 1.1 PHY
+	 * (this is the default setting anyway).
+	 */
+	 val &= ~CFGCHIP2_USB1PHYCLKMUX;
+	 val |=  CFGCHIP2_USB2PHYCLKMUX;
+
+	/*
+	 * We have to override VBUS/ID signals when MUSB is configured into the
+	 * host-only mode -- ID pin will float if no cable is connected, so the
+	 * controller won't be able to drive VBUS thinking that it's a B-device.
+	 * Otherwise, we want to use the OTG mode and enable VBUS comparators.
+	 */
+	val &= ~CFGCHIP2_OTGMODE;
+#ifdef	CONFIG_USB_MUSB_HOST
+	val |=  CFGCHIP2_FORCE_HOST;
+#else
+	val |=  CFGCHIP2_SESENDEN | CFGCHIP2_VBDTCTEN;
+#endif
+
+	/* configure the CFGCHIP2 register */
+	__raw_writel(val, cfg_chip2_base);
+
+	ret = davinci_cfg_reg_list(da850_usb11_pins);
+	if (ret) {
+		pr_warn("%s: USB 1.1 PinMux setup failed: %d\n", __func__, ret);
+		return;
+	}
+
+	ret = gpio_request_one(DA850_USB1_VBUS_PIN,
+			GPIOF_DIR_OUT, "USB1 VBUS");
+	if (ret < 0) {
+		pr_err("%s: failed to request GPIO for USB 1.1 port "
+			"power control: %d\n", __func__, ret);
+		return;
+	}
+
+	ret = gpio_request_one(DA850_USB1_OC_PIN,
+			GPIOF_DIR_IN, "USB1 OC");
+	if (ret < 0) {
+		pr_err("%s: failed to request GPIO for USB 1.1 port "
+			"over-current indicator: %d\n", __func__, ret);
+		goto usb11_setup_oc_fail;
+	}
+
+	ret = da8xx_register_usb11(&da850_usb11_pdata);
+	if (ret) {
+		pr_warn("%s: USB 1.1 registration failed: %d\n", __func__, ret);
+		goto usb11_setup_fail;
+	}
+
+	return;
+
+usb11_setup_fail:
+	gpio_free(DA850_USB1_OC_PIN);
+usb11_setup_oc_fail:
+	gpio_free(DA850_USB1_VBUS_PIN);
+}
+
+#else /* CONFIG_USB */
+
+static __init void da850_usb_init(void)
+{
+	return 0;
+}
+
+#endif /* CONFIG_USB */
+
 #define DA850EVM_SATA_REFCLKPN_RATE	(100 * 1000 * 1000)
 
 static __init void da850_evm_init(void)
@@ -1453,6 +1605,7 @@ static __init void da850_evm_init(void)
 	if (ret)
 		pr_warn("%s: I2C0 registration failed: %d\n", __func__, ret);
 
+	da850_usb_init();
 
 	ret = da8xx_register_watchdog();
 	if (ret)
-- 
1.7.12.1