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>

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>
Joachim Foerster · Greg Kroah-Hartman
1 parent 0f8fd43c42
Showing 3 changed files with 72 additions and 15 deletions Side-by-side Diff
drivers/usb/host/isp1760-hcd.c
drivers/usb/host/isp1760-hcd.h
drivers/usb/host/isp1760-if.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 @@
 	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 @@
 	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 @@
  
 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 @@
  
 	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) {
@@ -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 @@
 #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 {
@@ -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;
  
@@ -41,7 +48,12 @@
 	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)
 		return -ENXIO;
  
  
  
  
  
@@ -80,32 +92,57 @@
 	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 @@
  
 	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 @@
 	}
  
 	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;
...	...	@@ -24,6 +24,7 @@
24	24	#include <linux/timer.h>
25	25	#include <asm/unaligned.h>
26	26	#include <asm/cacheflush.h>
	27	+#include <linux/gpio.h>
27	28
28	29	#include "isp1760-hcd.h"
29	30
...	...	@@ -48,6 +49,8 @@
48	49	unsigned long reset_done;
49	50	unsigned long next_statechange;
50	51	unsigned int devflags;
	52	+
	53	+ int rst_gpio;
51	54	};
52	55
53	56	static inline struct isp1760_hcd hcd_to_priv(struct usb_hcd hcd)
...	...	@@ -433,6 +436,18 @@
433	436	int result;
434	437	u32 scratch, hwmode;
435	438
	439	+ /* low-level chip reset */
	440	+ if (gpio_is_valid(priv->rst_gpio)) {
	441	+ unsigned int rst_lvl;
	442	+
	443	+ rst_lvl = (priv->devflags &
	444	+ ISP1760_FLAG_RESET_ACTIVE_HIGH) ? 1 : 0;
	445	+
	446	+ gpio_set_value(priv->rst_gpio, rst_lvl);
	447	+ mdelay(50);
	448	+ gpio_set_value(priv->rst_gpio, !rst_lvl);
	449	+ }
	450	+
436	451	/* Setup HW Mode Control: This assumes a level active-low interrupt */
437	452	hwmode = HW_DATA_BUS_32BIT;
438	453
...	...	@@ -2207,6 +2222,7 @@
2207	2222
2208	2223	struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len,
2209	2224	int irq, unsigned long irqflags,
	2225	+ int rst_gpio,
2210	2226	struct device dev, const char busname,
2211	2227	unsigned int devflags)
2212	2228	{
...	...	@@ -2226,6 +2242,7 @@
2226	2242
2227	2243	priv = hcd_to_priv(hcd);
2228	2244	priv->devflags = devflags;
	2245	+ priv->rst_gpio = rst_gpio;
2229	2246	init_memory(priv);
2230	2247	hcd->regs = ioremap(res_start, res_len);
2231	2248	if (!hcd->regs) {
...	...	@@ -4,6 +4,7 @@
4	4	/* exports for if */
5	5	struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len,
6	6	int irq, unsigned long irqflags,
	7	+ int rst_gpio,
7	8	struct device dev, const char busname,
8	9	unsigned int devflags);
9	10	int init_kmem_once(void);
...	...	@@ -126,6 +127,7 @@
126	127	#define ISP1760_FLAG_ISP1761 0x00000040 /* Chip is ISP1761 */
127	128	#define ISP1760_FLAG_INTR_POL_HIGH 0x00000080 /* Interrupt polarity active high */
128	129	#define ISP1760_FLAG_INTR_EDGE_TRIG 0x00000100 /* Interrupt edge triggered */
	130	+#define ISP1760_FLAG_RESET_ACTIVE_HIGH 0x80000000 /* RESET GPIO active high */
129	131
130	132	/* chip memory management */
131	133	struct memory_chunk {
...	...	@@ -18,10 +18,12 @@
18	18	#include "isp1760-hcd.h"
19	19
20	20	#ifdef CONFIG_OF
	21	+#include <linux/slab.h>
21	22	#include <linux/of.h>
22	23	#include <linux/of_platform.h>
23	24	#include <linux/of_address.h>
24	25	#include <linux/of_irq.h>
	26	+#include <linux/of_gpio.h>
25	27	#endif
26	28
27	29	#ifdef CONFIG_PCI
28	30
...	...	@@ -29,9 +31,14 @@
29	31	#endif
30	32
31	33	#ifdef CONFIG_OF
	34	+struct isp1760 {
	35	+ struct usb_hcd *hcd;
	36	+ int rst_gpio;
	37	+};
	38	+
32	39	static int of_isp1760_probe(struct platform_device *dev)
33	40	{
34		- struct usb_hcd *hcd;
	41	+ struct isp1760 *drvdata;
35	42	struct device_node *dp = dev->dev.of_node;
36	43	struct resource *res;
37	44	struct resource memory;
38	45
...	...	@@ -41,7 +48,12 @@
41	48	int ret;
42	49	const unsigned int *prop;
43	50	unsigned int devflags = 0;
	51	+ enum of_gpio_flags gpio_flags;
44	52
	53	+ drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
	54	+ if (!drvdata)
	55	+ return -ENOMEM;
	56	+
45	57	ret = of_address_to_resource(dp, 0, &memory);
46	58	if (ret)
47	59	return -ENXIO;
48	60
49	61
50	62
51	63
52	64
...	...	@@ -80,32 +92,57 @@
80	92	if (of_get_property(dp, "dreq-polarity", NULL) != NULL)
81	93	devflags \|= ISP1760_FLAG_DREQ_POL_HIGH;
82	94
83		- hcd = isp1760_register(memory.start, res_len, virq,
84		- IRQF_SHARED, &dev->dev, dev_name(&dev->dev),
85		- devflags);
86		- if (IS_ERR(hcd)) {
87		- ret = PTR_ERR(hcd);
88		- goto release_reg;
	95	+ drvdata->rst_gpio = of_get_gpio_flags(dp, 0, &gpio_flags);
	96	+ if (gpio_is_valid(drvdata->rst_gpio)) {
	97	+ ret = gpio_request(drvdata->rst_gpio, dev_name(&dev->dev));
	98	+ if (!ret) {
	99	+ if (!(gpio_flags & OF_GPIO_ACTIVE_LOW)) {
	100	+ devflags \|= ISP1760_FLAG_RESET_ACTIVE_HIGH;
	101	+ gpio_direction_output(drvdata->rst_gpio, 0);
	102	+ } else {
	103	+ gpio_direction_output(drvdata->rst_gpio, 1);
	104	+ }
	105	+ } else {
	106	+ drvdata->rst_gpio = ret;
	107	+ }
89	108	}
90	109
91		- dev_set_drvdata(&dev->dev, hcd);
	110	+ drvdata->hcd = isp1760_register(memory.start, res_len, virq,
	111	+ IRQF_SHARED, drvdata->rst_gpio,
	112	+ &dev->dev, dev_name(&dev->dev),
	113	+ devflags);
	114	+ if (IS_ERR(drvdata->hcd)) {
	115	+ ret = PTR_ERR(drvdata->hcd);
	116	+ goto free_gpio;
	117	+ }
	118	+
	119	+ dev_set_drvdata(&dev->dev, drvdata);
92	120	return ret;
93	121
	122	+free_gpio:
	123	+ if (gpio_is_valid(drvdata->rst_gpio))
	124	+ gpio_free(drvdata->rst_gpio);
94	125	release_reg:
95	126	release_mem_region(memory.start, res_len);
	127	+ kfree(drvdata);
96	128	return ret;
97	129	}
98	130
99	131	static int of_isp1760_remove(struct platform_device *dev)
100	132	{
101		- struct usb_hcd *hcd = dev_get_drvdata(&dev->dev);
	133	+ struct isp1760 *drvdata = dev_get_drvdata(&dev->dev);
102	134
103	135	dev_set_drvdata(&dev->dev, NULL);
104	136
105		- usb_remove_hcd(hcd);
106		- iounmap(hcd->regs);
107		- release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
108		- usb_put_hcd(hcd);
	137	+ usb_remove_hcd(drvdata->hcd);
	138	+ iounmap(drvdata->hcd->regs);
	139	+ release_mem_region(drvdata->hcd->rsrc_start, drvdata->hcd->rsrc_len);
	140	+ usb_put_hcd(drvdata->hcd);
	141	+
	142	+ if (gpio_is_valid(drvdata->rst_gpio))
	143	+ gpio_free(drvdata->rst_gpio);
	144	+
	145	+ kfree(drvdata);
109	146	return 0;
110	147	}
111	148
...	...	@@ -242,7 +279,7 @@
242	279
243	280	dev->dev.dma_mask = NULL;
244	281	hcd = isp1760_register(pci_mem_phy0, memlength, dev->irq,
245		- IRQF_SHARED, &dev->dev, dev_name(&dev->dev),
	282	+ IRQF_SHARED, -ENOENT, &dev->dev, dev_name(&dev->dev),
246	283	devflags);
247	284	if (IS_ERR(hcd)) {
248	285	ret_status = -ENODEV;
...	...	@@ -353,7 +390,8 @@
353	390	}
354	391
355	392	hcd = isp1760_register(mem_res->start, mem_size, irq_res->start,
356		- irqflags, &pdev->dev, dev_name(&pdev->dev), devflags);
	393	+ irqflags, -ENOENT,
	394	+ &pdev->dev, dev_name(&pdev->dev), devflags);
357	395	if (IS_ERR(hcd)) {
358	396	pr_warning("isp1760: Failed to register the HCD device\n");
359	397	ret = -ENODEV;