Commit 3a7655fc authored by Joachim Foerster's avatar Joachim Foerster Committed by Greg Kroah-Hartman
Browse files

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: default avatarJoachim Foerster <joachim.foerster@missinglinkelectronics.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 0f8fd43c

drivers/usb/host/isp1760-hcd.c

+17 −0
Original line number Diff line number Diff line
@@ -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) {

drivers/usb/host/isp1760-hcd.h

+2 −0
Original line number Diff line number Diff line
@@ -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 {

drivers/usb/host/isp1760-if.c

+53 −15
Original line number Diff line number Diff line
@@ -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),

	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;

		}

	}



	drvdata->hcd = isp1760_register(memory.start, res_len, virq,

					IRQF_SHARED, drvdata->rst_gpio,

					&dev->dev, dev_name(&dev->dev),

					devflags);

	if (IS_ERR(hcd)) {

		ret = PTR_ERR(hcd);

		goto release_reg;

	if (IS_ERR(drvdata->hcd)) {

		ret = PTR_ERR(drvdata->hcd);

		goto free_gpio;

	}



	dev_set_drvdata(&dev->dev, hcd);

	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;

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