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author | Joachim Foerster <joachim.foerster@missinglinkelectronics.com> | 2011-10-19 14:18:41 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-10-19 13:29:06 -0700 |
commit | 3a7655fcb210b349111251689d0a56b7250885ea (patch) | |
tree | b909f3f73d89d1af8807036a3922a19aca41b514 | |
parent | 0f8fd43c42f2cc249943be76a4db0d058c16b6dc (diff) | |
download | linux-3a7655fcb210b349111251689d0a56b7250885ea.tar.gz linux-3a7655fcb210b349111251689d0a56b7250885ea.tar.bz2 linux-3a7655fcb210b349111251689d0a56b7250885ea.zip |
usb/isp1760: Allow to optionally trigger low-level chip reset via GPIOLIB.
Properly triggering the reset wire is necessary with the ISP1761 used
on Terasic DE4 Altera-FPGA boards using a NIOS2 processor, for example.
This is an optional implementation for the OF binding only. The other
bindings just pass an invalid GPIO to the isp1760_register() routine.
Example, usage in DTS:
gpios = <&pio_isp1761rst_0 0 1>;
to point to a GPIO controller from within the ISP1761 node: GPIO 0, active low.
Signed-off-by: Joachim Foerster <joachim.foerster@missinglinkelectronics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/usb/host/isp1760-hcd.c | 17 | ||||
-rw-r--r-- | drivers/usb/host/isp1760-hcd.h | 2 | ||||
-rw-r--r-- | drivers/usb/host/isp1760-if.c | 68 |
3 files changed, 72 insertions, 15 deletions
diff --git a/drivers/usb/host/isp1760-hcd.c b/drivers/usb/host/isp1760-hcd.c index 5b08bd743acc..27dfab80ed8f 100644 --- a/drivers/usb/host/isp1760-hcd.c +++ b/drivers/usb/host/isp1760-hcd.c @@ -24,6 +24,7 @@ #include <linux/timer.h> #include <asm/unaligned.h> #include <asm/cacheflush.h> +#include <linux/gpio.h> #include "isp1760-hcd.h" @@ -48,6 +49,8 @@ struct isp1760_hcd { unsigned long reset_done; unsigned long next_statechange; unsigned int devflags; + + int rst_gpio; }; static inline struct isp1760_hcd *hcd_to_priv(struct usb_hcd *hcd) @@ -433,6 +436,18 @@ static int isp1760_hc_setup(struct usb_hcd *hcd) int result; u32 scratch, hwmode; + /* low-level chip reset */ + if (gpio_is_valid(priv->rst_gpio)) { + unsigned int rst_lvl; + + rst_lvl = (priv->devflags & + ISP1760_FLAG_RESET_ACTIVE_HIGH) ? 1 : 0; + + gpio_set_value(priv->rst_gpio, rst_lvl); + mdelay(50); + gpio_set_value(priv->rst_gpio, !rst_lvl); + } + /* Setup HW Mode Control: This assumes a level active-low interrupt */ hwmode = HW_DATA_BUS_32BIT; @@ -2207,6 +2222,7 @@ void deinit_kmem_cache(void) struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len, int irq, unsigned long irqflags, + int rst_gpio, struct device *dev, const char *busname, unsigned int devflags) { @@ -2226,6 +2242,7 @@ struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len, priv = hcd_to_priv(hcd); priv->devflags = devflags; + priv->rst_gpio = rst_gpio; init_memory(priv); hcd->regs = ioremap(res_start, res_len); if (!hcd->regs) { diff --git a/drivers/usb/host/isp1760-hcd.h b/drivers/usb/host/isp1760-hcd.h index fda0f2d54e3d..33dc79ccaa6b 100644 --- a/drivers/usb/host/isp1760-hcd.h +++ b/drivers/usb/host/isp1760-hcd.h @@ -4,6 +4,7 @@ /* exports for if */ struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len, int irq, unsigned long irqflags, + int rst_gpio, struct device *dev, const char *busname, unsigned int devflags); int init_kmem_once(void); @@ -126,6 +127,7 @@ typedef void (packet_enqueue)(struct usb_hcd *hcd, struct isp1760_qh *qh, #define ISP1760_FLAG_ISP1761 0x00000040 /* Chip is ISP1761 */ #define ISP1760_FLAG_INTR_POL_HIGH 0x00000080 /* Interrupt polarity active high */ #define ISP1760_FLAG_INTR_EDGE_TRIG 0x00000100 /* Interrupt edge triggered */ +#define ISP1760_FLAG_RESET_ACTIVE_HIGH 0x80000000 /* RESET GPIO active high */ /* chip memory management */ struct memory_chunk { diff --git a/drivers/usb/host/isp1760-if.c b/drivers/usb/host/isp1760-if.c index 791792db6e12..2c7fc830c9e4 100644 --- a/drivers/usb/host/isp1760-if.c +++ b/drivers/usb/host/isp1760-if.c @@ -18,10 +18,12 @@ #include "isp1760-hcd.h" #ifdef CONFIG_OF +#include <linux/slab.h> #include <linux/of.h> #include <linux/of_platform.h> #include <linux/of_address.h> #include <linux/of_irq.h> +#include <linux/of_gpio.h> #endif #ifdef CONFIG_PCI @@ -29,9 +31,14 @@ #endif #ifdef CONFIG_OF +struct isp1760 { + struct usb_hcd *hcd; + int rst_gpio; +}; + static int of_isp1760_probe(struct platform_device *dev) { - struct usb_hcd *hcd; + struct isp1760 *drvdata; struct device_node *dp = dev->dev.of_node; struct resource *res; struct resource memory; @@ -41,6 +48,11 @@ static int of_isp1760_probe(struct platform_device *dev) int ret; const unsigned int *prop; unsigned int devflags = 0; + enum of_gpio_flags gpio_flags; + + drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL); + if (!drvdata) + return -ENOMEM; ret = of_address_to_resource(dp, 0, &memory); if (ret) @@ -80,32 +92,57 @@ static int of_isp1760_probe(struct platform_device *dev) if (of_get_property(dp, "dreq-polarity", NULL) != NULL) devflags |= ISP1760_FLAG_DREQ_POL_HIGH; - hcd = isp1760_register(memory.start, res_len, virq, - IRQF_SHARED, &dev->dev, dev_name(&dev->dev), - devflags); - if (IS_ERR(hcd)) { - ret = PTR_ERR(hcd); - goto release_reg; + drvdata->rst_gpio = of_get_gpio_flags(dp, 0, &gpio_flags); + if (gpio_is_valid(drvdata->rst_gpio)) { + ret = gpio_request(drvdata->rst_gpio, dev_name(&dev->dev)); + if (!ret) { + if (!(gpio_flags & OF_GPIO_ACTIVE_LOW)) { + devflags |= ISP1760_FLAG_RESET_ACTIVE_HIGH; + gpio_direction_output(drvdata->rst_gpio, 0); + } else { + gpio_direction_output(drvdata->rst_gpio, 1); + } + } else { + drvdata->rst_gpio = ret; + } } - dev_set_drvdata(&dev->dev, hcd); + drvdata->hcd = isp1760_register(memory.start, res_len, virq, + IRQF_SHARED, drvdata->rst_gpio, + &dev->dev, dev_name(&dev->dev), + devflags); + if (IS_ERR(drvdata->hcd)) { + ret = PTR_ERR(drvdata->hcd); + goto free_gpio; + } + + dev_set_drvdata(&dev->dev, drvdata); return ret; +free_gpio: + if (gpio_is_valid(drvdata->rst_gpio)) + gpio_free(drvdata->rst_gpio); release_reg: release_mem_region(memory.start, res_len); + kfree(drvdata); return ret; } static int of_isp1760_remove(struct platform_device *dev) { - struct usb_hcd *hcd = dev_get_drvdata(&dev->dev); + struct isp1760 *drvdata = dev_get_drvdata(&dev->dev); dev_set_drvdata(&dev->dev, NULL); - usb_remove_hcd(hcd); - iounmap(hcd->regs); - release_mem_region(hcd->rsrc_start, hcd->rsrc_len); - usb_put_hcd(hcd); + usb_remove_hcd(drvdata->hcd); + iounmap(drvdata->hcd->regs); + release_mem_region(drvdata->hcd->rsrc_start, drvdata->hcd->rsrc_len); + usb_put_hcd(drvdata->hcd); + + if (gpio_is_valid(drvdata->rst_gpio)) + gpio_free(drvdata->rst_gpio); + + kfree(drvdata); return 0; } @@ -242,7 +279,7 @@ static int __devinit isp1761_pci_probe(struct pci_dev *dev, dev->dev.dma_mask = NULL; hcd = isp1760_register(pci_mem_phy0, memlength, dev->irq, - IRQF_SHARED, &dev->dev, dev_name(&dev->dev), + IRQF_SHARED, -ENOENT, &dev->dev, dev_name(&dev->dev), devflags); if (IS_ERR(hcd)) { ret_status = -ENODEV; @@ -353,7 +390,8 @@ static int __devinit isp1760_plat_probe(struct platform_device *pdev) } hcd = isp1760_register(mem_res->start, mem_size, irq_res->start, - irqflags, &pdev->dev, dev_name(&pdev->dev), devflags); + irqflags, -ENOENT, + &pdev->dev, dev_name(&pdev->dev), devflags); if (IS_ERR(hcd)) { pr_warning("isp1760: Failed to register the HCD device\n"); ret = -ENODEV; |