openwrt/target/linux/pxa/patches-2.6.21/011-proc-gpio.patch

319 lines
7.7 KiB
Diff

--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -505,6 +505,8 @@ config PCI_HOST_VIA82C505
depends on PCI && ARCH_SHARK
default y
+source "drivers/gpio/Kconfig"
+
source "drivers/pci/Kconfig"
source "drivers/pcmcia/Kconfig"
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -81,3 +81,4 @@ obj-$(CONFIG_GENERIC_TIME) += clocksourc
obj-$(CONFIG_DMA_ENGINE) += dma/
obj-$(CONFIG_HID) += hid/
obj-$(CONFIG_PPC_PS3) += ps3/
+obj-$(CONFIG_PROC_GPIO) += gpio/
--- /dev/null
+++ b/drivers/gpio/Kconfig
@@ -0,0 +1,13 @@
+config PROC_GPIO
+ tristate "GPIO /proc interface"
+ depends on PXA25x || PXA27x
+ help
+ This enables an interface under /proc/gpio which allows reading or setting
+ of any GPIO, and also changing the GPIO alt function mode of any line.
+
+config PROC_GPIO_DEBUG
+ boolean "Enable /proc/gpio debug logging"
+ depends on PROC_GPIO
+ help
+ This enables printk logging of activity done through /proc/gpio
+
--- /dev/null
+++ b/drivers/gpio/Makefile
@@ -0,0 +1,2 @@
+# Expose GPIOs under /proc
+obj-$(CONFIG_PROC_GPIO) += proc_gpio.o
--- /dev/null
+++ b/drivers/gpio/proc_gpio.c
@@ -0,0 +1,276 @@
+/*
+ *
+ * PXA25x GPIOs exposed under /proc for reading and writing
+ * They will show up under /proc/gpio/NN
+ *
+ * Based on patch 1773/1 in the arm kernel patch repository at arm.linux.co.uk
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+
+#include <asm/hardware.h>
+#include <asm/arch/pxa-regs.h>
+#include <asm/uaccess.h>
+
+static struct proc_dir_entry *proc_gpio_parent;
+static struct proc_dir_entry *proc_gpios[PXA_LAST_GPIO + 1];
+
+typedef struct
+{
+ int gpio;
+ char name[32];
+} gpio_summary_type;
+
+static gpio_summary_type gpio_summaries[PXA_LAST_GPIO + 1];
+
+static int proc_gpio_write(struct file *file, const char __user *buf,
+ unsigned long count, void *data)
+{
+ char *cur, lbuf[count + 1];
+ gpio_summary_type *summary = data;
+ u32 altfn, direction, setclear, gafr;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ memset(lbuf, 0, count + 1);
+
+ if (copy_from_user(lbuf, buf, count))
+ return -EFAULT;
+
+ cur = lbuf;
+
+ // Initialize to current state
+ altfn = ((GAFR(summary->gpio) >> ((summary->gpio & 0x0f) << 0x01)) & 0x03);
+ direction = GPDR(summary->gpio) & GPIO_bit(summary->gpio);
+ setclear = GPLR(summary->gpio) & GPIO_bit(summary->gpio);
+ while(1)
+ {
+ // We accept options: {GPIO|AF1|AF2|AF3}, {set|clear}, {in|out}
+ // Anything else is an error
+ while(cur[0] && (isspace(cur[0]) || ispunct(cur[0]))) cur = &(cur[1]);
+
+ if('\0' == cur[0]) break;
+
+ // Ok, so now we're pointing at the start of something
+ switch(cur[0])
+ {
+ case 'G':
+ // Check that next is "PIO" -- '\0' will cause safe short-circuit if end of buf
+ if(!(cur[1] == 'P' && cur[2] == 'I' && cur[3] == 'O')) goto parse_error;
+ // Ok, so set this GPIO to GPIO (non-ALT) function
+ altfn = 0;
+ cur = &(cur[4]);
+ break;
+ case 'A':
+ if(!(cur[1] == 'F' && cur[2] >= '1' && cur[2] <= '3')) goto parse_error;
+ altfn = cur[2] - '0';
+ cur = &(cur[3]);
+ break;
+ case 's':
+ if(!(cur[1] == 'e' && cur[2] == 't')) goto parse_error;
+ setclear = 1;
+ cur = &(cur[3]);
+ break;
+ case 'c':
+ if(!(cur[1] == 'l' && cur[2] == 'e' && cur[3] == 'a' && cur[4] == 'r')) goto parse_error;
+ setclear = 0;
+ cur = &(cur[5]);
+ break;
+ case 'i':
+ if(!(cur[1] == 'n')) goto parse_error;
+ direction = 0;
+ cur = &(cur[2]);
+ break;
+ case 'o':
+ if(!(cur[1] == 'u' && cur[2] == 't')) goto parse_error;
+ direction = 1;
+ cur = &(cur[3]);
+ break;
+ default: goto parse_error;
+ }
+ }
+ // Ok, now set gpio mode and value
+ if(direction)
+ GPDR(summary->gpio) |= GPIO_bit(summary->gpio);
+ else
+ GPDR(summary->gpio) &= ~GPIO_bit(summary->gpio);
+
+ gafr = GAFR(summary->gpio) & ~(0x3 << (((summary->gpio) & 0xf)*2));
+ GAFR(summary->gpio) = gafr | (altfn << (((summary->gpio) & 0xf)*2));
+
+ if(direction && !altfn)
+ {
+ if(setclear) GPSR(summary->gpio) = GPIO_bit(summary->gpio);
+ else GPCR(summary->gpio) = GPIO_bit(summary->gpio);
+ }
+
+#ifdef CONFIG_PROC_GPIO_DEBUG
+ printk(KERN_INFO "Set (%s,%s,%s) via /proc/gpio/%s\n",altfn ? (altfn == 1 ? "AF1" : (altfn == 2 ? "AF2" : "AF3")) : "GPIO",
+ direction ? "out" : "in",
+ setclear ? "set" : "clear",
+ summary->name);
+#endif
+
+ return count;
+
+parse_error:
+ printk(KERN_CRIT "Parse error: Expect \"[GPIO|AF1|AF2|AF3]|[set|clear]|[in|out] ...\"\n");
+ return -EINVAL;
+}
+
+static int proc_gpio_read(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ char *p = page;
+ gpio_summary_type *summary = data;
+ int len, i, af;
+ i = summary->gpio;
+
+ p += sprintf(p, "%d\t%s\t%s\t%s\n", i,
+ (af = ((GAFR(i) >> ((i & 0x0f) << 0x01)) & 0x03)) ? (af == 1 ? "AF1" : (af == 2 ? "AF2" : "AF3")) : "GPIO",
+ (GPDR(i) & GPIO_bit(i)) ? "out" : "in",
+ (GPLR(i) & GPIO_bit(i)) ? "set" : "clear");
+
+ len = (p - page) - off;
+
+ if(len < 0)
+ {
+ len = 0;
+ }
+
+ *eof = (len <= count) ? 1 : 0;
+ *start = page + off;
+
+ return len;
+}
+
+
+#ifdef CONFIG_PXA25x
+static const char const *GAFR_DESC[] = { "GAFR0_L", "GAFR0_U", "GAFR1_L", "GAFR1_U", "GAFR2_L", "GAFR2_U" };
+#elif defined(CONFIG_PXA27x)
+static const char const *GAFR_DESC[] = { "GAFR0_L", "GAFR0_U", "GAFR1_L", "GAFR1_U", "GAFR2_L", "GAFR2_U", "GAFR3_L", "GAFR3_U" };
+#endif
+
+static int proc_gafr_read(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ char *p = page;
+ int i, len;
+
+ for(i=0; i<ARRAY_SIZE(GAFR_DESC); i++)
+ {
+ p += sprintf(p, "%s: %08x\n", GAFR_DESC[i], GAFR(i*16));
+ }
+
+ len = (p - page) - off;
+
+ if(len < 0)
+ {
+ len = 0;
+ }
+
+ *eof = (len <= count) ? 1 : 0;
+ *start = page + off;
+
+ return len;
+}
+
+static int proc_gpdr_read(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ char *p = page;
+ int i, len;
+
+ for(i=0; i<=2; i++)
+ {
+ p += sprintf(p, "GPDR%d: %08x\n", i, GPDR(i * 32));
+ }
+
+ len = (p - page) - off;
+
+ if(len < 0)
+ {
+ len = 0;
+ }
+
+ *eof = (len <= count) ? 1 : 0;
+ *start = page + off;
+
+ return len;
+}
+
+static int proc_gplr_read(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ char *p = page;
+ int i, len;
+
+ for(i=0; i<=2; i++)
+ {
+ p += sprintf(p, "GPLR%d: %08x\n", i, GPLR(i * 32));
+ }
+
+ len = (p - page) - off;
+
+ if(len < 0)
+ {
+ len = 0;
+ }
+
+ *eof = (len <= count) ? 1 : 0;
+ *start = page + off;
+
+ return len;
+}
+
+static int __init gpio_init(void)
+{
+ int i;
+
+ proc_gpio_parent = create_proc_entry("gpio", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
+ if(!proc_gpio_parent) return 0;
+
+ for(i=0; i < (PXA_LAST_GPIO+1); i++)
+ {
+ gpio_summaries[i].gpio = i;
+ sprintf(gpio_summaries[i].name, "GPIO%d", i);
+ proc_gpios[i] = create_proc_entry(gpio_summaries[i].name, 0644, proc_gpio_parent);
+ if(proc_gpios[i])
+ {
+ proc_gpios[i]->data = &gpio_summaries[i];
+ proc_gpios[i]->read_proc = proc_gpio_read;
+ proc_gpios[i]->write_proc = proc_gpio_write;
+ }
+ }
+
+ create_proc_read_entry("GAFR", 0444, proc_gpio_parent, proc_gafr_read, NULL);
+ create_proc_read_entry("GPDR", 0444, proc_gpio_parent, proc_gpdr_read, NULL);
+ create_proc_read_entry("GPLR", 0444, proc_gpio_parent, proc_gplr_read, NULL);
+
+ return 0;
+}
+
+static void gpio_exit(void)
+{
+ int i;
+
+ remove_proc_entry("GAFR", proc_gpio_parent);
+ remove_proc_entry("GPDR", proc_gpio_parent);
+ remove_proc_entry("GPLR", proc_gpio_parent);
+
+ for(i=0; i < (PXA_LAST_GPIO+1); i++)
+ {
+ if(proc_gpios[i]) remove_proc_entry(gpio_summaries[i].name, proc_gpio_parent);
+ }
+ if(proc_gpio_parent) remove_proc_entry("gpio", NULL);
+}
+
+module_init(gpio_init);
+module_exit(gpio_exit);
+MODULE_LICENSE("GPL");