386 lines
12 KiB
Diff
386 lines
12 KiB
Diff
From 4a703aa1cc152189682c173bb4d89ef8f9da6c21 Mon Sep 17 00:00:00 2001
|
|
From: popcornmix <popcornmix@gmail.com>
|
|
Date: Wed, 8 May 2013 11:46:50 +0100
|
|
Subject: [PATCH 031/148] enabling the realtime clock 1-wire chip DS1307 and
|
|
1-wire on GPIO4 (as a module)
|
|
|
|
1-wire: Add support for configuring pin for w1-gpio kernel module
|
|
See: https://github.com/raspberrypi/linux/pull/457
|
|
|
|
Add bitbanging pullups, use them for w1-gpio
|
|
|
|
Allows parasite power to work, uses module option pullup=1
|
|
|
|
bcm2708: Ensure 1-wire pullup is disabled by default, and expose as module parameter
|
|
|
|
Signed-off-by: Alex J Lennon <ajlennon@dynamicdevices.co.uk>
|
|
|
|
w1-gpio: Add gpiopin module parameter and correctly free up gpio pull-up pin, if set
|
|
|
|
Signed-off-by: Alex J Lennon <ajlennon@dynamicdevices.co.uk>
|
|
|
|
w1-gpio: Sort out the pullup/parasitic power tangle
|
|
---
|
|
arch/arm/mach-bcm2708/bcm2708.c | 29 +++++++++++++++++
|
|
arch/arm/mach-bcm2709/bcm2709.c | 29 +++++++++++++++++
|
|
drivers/w1/masters/w1-gpio.c | 69 +++++++++++++++++++++++++++++++++++++----
|
|
drivers/w1/w1.h | 6 ++++
|
|
drivers/w1/w1_int.c | 14 +++++++++
|
|
drivers/w1/w1_io.c | 18 +++++++++--
|
|
include/linux/w1-gpio.h | 1 +
|
|
7 files changed, 157 insertions(+), 9 deletions(-)
|
|
|
|
--- a/arch/arm/mach-bcm2708/bcm2708.c
|
|
+++ b/arch/arm/mach-bcm2708/bcm2708.c
|
|
@@ -36,6 +36,7 @@
|
|
#include <linux/of_platform.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/gpio/machine.h>
|
|
+#include <linux/w1-gpio.h>
|
|
|
|
#include <linux/version.h>
|
|
#include <linux/clkdev.h>
|
|
@@ -77,12 +78,19 @@
|
|
*/
|
|
#define DMA_MASK_BITS_COMMON 32
|
|
|
|
+// use GPIO 4 for the one-wire GPIO pin, if enabled
|
|
+#define W1_GPIO 4
|
|
+// ensure one-wire GPIO pullup is disabled by default
|
|
+#define W1_PULLUP -1
|
|
+
|
|
/* command line parameters */
|
|
static unsigned boardrev, serial;
|
|
static unsigned uart_clock = UART0_CLOCK;
|
|
static unsigned disk_led_gpio = 16;
|
|
static unsigned disk_led_active_low = 1;
|
|
static unsigned reboot_part = 0;
|
|
+static unsigned w1_gpio_pin = W1_GPIO;
|
|
+static unsigned w1_gpio_pullup = W1_PULLUP;
|
|
static bool vc_i2c_override = false;
|
|
|
|
static unsigned use_dt = 0;
|
|
@@ -303,6 +311,20 @@ static struct platform_device bcm2708_dm
|
|
.num_resources = ARRAY_SIZE(bcm2708_dmaengine_resources),
|
|
};
|
|
|
|
+#if defined(CONFIG_W1_MASTER_GPIO) || defined(CONFIG_W1_MASTER_GPIO_MODULE)
|
|
+static struct w1_gpio_platform_data w1_gpio_pdata = {
|
|
+ .pin = W1_GPIO,
|
|
+ .ext_pullup_enable_pin = W1_PULLUP,
|
|
+ .is_open_drain = 0,
|
|
+};
|
|
+
|
|
+static struct platform_device w1_device = {
|
|
+ .name = "w1-gpio",
|
|
+ .id = -1,
|
|
+ .dev.platform_data = &w1_gpio_pdata,
|
|
+};
|
|
+#endif
|
|
+
|
|
static u64 fb_dmamask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON);
|
|
|
|
static struct platform_device bcm2708_fb_device = {
|
|
@@ -729,6 +751,11 @@ void __init bcm2708_init(void)
|
|
#ifdef CONFIG_BCM2708_GPIO
|
|
bcm_register_device_dt(&bcm2708_gpio_device);
|
|
#endif
|
|
+#if defined(CONFIG_W1_MASTER_GPIO) || defined(CONFIG_W1_MASTER_GPIO_MODULE)
|
|
+ w1_gpio_pdata.pin = w1_gpio_pin;
|
|
+ w1_gpio_pdata.ext_pullup_enable_pin = w1_gpio_pullup;
|
|
+ bcm_register_device_dt(&w1_device);
|
|
+#endif
|
|
bcm_register_device_dt(&bcm2708_fb_device);
|
|
bcm_register_device_dt(&bcm2708_usb_device);
|
|
|
|
@@ -942,5 +969,7 @@ module_param(uart_clock, uint, 0644);
|
|
module_param(disk_led_gpio, uint, 0644);
|
|
module_param(disk_led_active_low, uint, 0644);
|
|
module_param(reboot_part, uint, 0644);
|
|
+module_param(w1_gpio_pin, uint, 0644);
|
|
+module_param(w1_gpio_pullup, uint, 0644);
|
|
module_param(vc_i2c_override, bool, 0644);
|
|
MODULE_PARM_DESC(vc_i2c_override, "Allow the use of VC's I2C peripheral.");
|
|
--- a/arch/arm/mach-bcm2709/bcm2709.c
|
|
+++ b/arch/arm/mach-bcm2709/bcm2709.c
|
|
@@ -36,6 +36,7 @@
|
|
#include <linux/of_platform.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/gpio/machine.h>
|
|
+#include <linux/w1-gpio.h>
|
|
|
|
#include <linux/version.h>
|
|
#include <linux/clkdev.h>
|
|
@@ -79,12 +80,19 @@
|
|
*/
|
|
#define DMA_MASK_BITS_COMMON 32
|
|
|
|
+// use GPIO 4 for the one-wire GPIO pin, if enabled
|
|
+#define W1_GPIO 4
|
|
+// ensure one-wire GPIO pullup is disabled by default
|
|
+#define W1_PULLUP -1
|
|
+
|
|
/* command line parameters */
|
|
static unsigned boardrev, serial;
|
|
static unsigned uart_clock = UART0_CLOCK;
|
|
static unsigned disk_led_gpio = 16;
|
|
static unsigned disk_led_active_low = 1;
|
|
static unsigned reboot_part = 0;
|
|
+static unsigned w1_gpio_pin = W1_GPIO;
|
|
+static unsigned w1_gpio_pullup = W1_PULLUP;
|
|
static bool vc_i2c_override = false;
|
|
|
|
static unsigned use_dt = 0;
|
|
@@ -313,6 +321,20 @@ static struct platform_device bcm2708_dm
|
|
.num_resources = ARRAY_SIZE(bcm2708_dmaengine_resources),
|
|
};
|
|
|
|
+#if defined(CONFIG_W1_MASTER_GPIO) || defined(CONFIG_W1_MASTER_GPIO_MODULE)
|
|
+static struct w1_gpio_platform_data w1_gpio_pdata = {
|
|
+ .pin = W1_GPIO,
|
|
+ .ext_pullup_enable_pin = W1_PULLUP,
|
|
+ .is_open_drain = 0,
|
|
+};
|
|
+
|
|
+static struct platform_device w1_device = {
|
|
+ .name = "w1-gpio",
|
|
+ .id = -1,
|
|
+ .dev.platform_data = &w1_gpio_pdata,
|
|
+};
|
|
+#endif
|
|
+
|
|
static u64 fb_dmamask = DMA_BIT_MASK(DMA_MASK_BITS_COMMON);
|
|
|
|
static struct platform_device bcm2708_fb_device = {
|
|
@@ -749,6 +771,11 @@ void __init bcm2709_init(void)
|
|
#ifdef CONFIG_BCM2708_GPIO
|
|
bcm_register_device_dt(&bcm2708_gpio_device);
|
|
#endif
|
|
+#if defined(CONFIG_W1_MASTER_GPIO) || defined(CONFIG_W1_MASTER_GPIO_MODULE)
|
|
+ w1_gpio_pdata.pin = w1_gpio_pin;
|
|
+ w1_gpio_pdata.ext_pullup_enable_pin = w1_gpio_pullup;
|
|
+ bcm_register_device_dt(&w1_device);
|
|
+#endif
|
|
bcm_register_device_dt(&bcm2708_fb_device);
|
|
bcm_register_device_dt(&bcm2708_usb_device);
|
|
|
|
@@ -1110,5 +1137,7 @@ module_param(uart_clock, uint, 0644);
|
|
module_param(disk_led_gpio, uint, 0644);
|
|
module_param(disk_led_active_low, uint, 0644);
|
|
module_param(reboot_part, uint, 0644);
|
|
+module_param(w1_gpio_pin, uint, 0644);
|
|
+module_param(w1_gpio_pullup, uint, 0644);
|
|
module_param(vc_i2c_override, bool, 0644);
|
|
MODULE_PARM_DESC(vc_i2c_override, "Allow the use of VC's I2C peripheral.");
|
|
--- a/drivers/w1/masters/w1-gpio.c
|
|
+++ b/drivers/w1/masters/w1-gpio.c
|
|
@@ -23,6 +23,19 @@
|
|
#include "../w1.h"
|
|
#include "../w1_int.h"
|
|
|
|
+static int w1_gpio_pullup = 0;
|
|
+static int w1_gpio_pullup_orig = 0;
|
|
+module_param_named(pullup, w1_gpio_pullup, int, 0);
|
|
+MODULE_PARM_DESC(pullup, "Enable parasitic power (power on data) mode");
|
|
+static int w1_gpio_pullup_pin = -1;
|
|
+static int w1_gpio_pullup_pin_orig = -1;
|
|
+module_param_named(extpullup, w1_gpio_pullup_pin, int, 0);
|
|
+MODULE_PARM_DESC(extpullup, "GPIO external pullup pin number");
|
|
+static int w1_gpio_pin = -1;
|
|
+static int w1_gpio_pin_orig = -1;
|
|
+module_param_named(gpiopin, w1_gpio_pin, int, 0);
|
|
+MODULE_PARM_DESC(gpiopin, "GPIO pin number");
|
|
+
|
|
static u8 w1_gpio_set_pullup(void *data, int delay)
|
|
{
|
|
struct w1_gpio_platform_data *pdata = data;
|
|
@@ -67,6 +80,16 @@ static u8 w1_gpio_read_bit(void *data)
|
|
return gpio_get_value(pdata->pin) ? 1 : 0;
|
|
}
|
|
|
|
+static void w1_gpio_bitbang_pullup(void *data, u8 on)
|
|
+{
|
|
+ struct w1_gpio_platform_data *pdata = data;
|
|
+
|
|
+ if (on)
|
|
+ gpio_direction_output(pdata->pin, 1);
|
|
+ else
|
|
+ gpio_direction_input(pdata->pin);
|
|
+}
|
|
+
|
|
#if defined(CONFIG_OF)
|
|
static const struct of_device_id w1_gpio_dt_ids[] = {
|
|
{ .compatible = "w1-gpio" },
|
|
@@ -80,6 +103,7 @@ static int w1_gpio_probe_dt(struct platf
|
|
struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
|
|
struct device_node *np = pdev->dev.of_node;
|
|
int gpio;
|
|
+ u32 value;
|
|
|
|
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
|
|
if (!pdata)
|
|
@@ -88,6 +112,9 @@ static int w1_gpio_probe_dt(struct platf
|
|
if (of_get_property(np, "linux,open-drain", NULL))
|
|
pdata->is_open_drain = 1;
|
|
|
|
+ if (of_property_read_u32(np, "rpi,parasitic-power", &value) == 0)
|
|
+ pdata->parasitic_power = (value != 0);
|
|
+
|
|
gpio = of_get_gpio(np, 0);
|
|
if (gpio < 0) {
|
|
if (gpio != -EPROBE_DEFER)
|
|
@@ -103,7 +130,7 @@ static int w1_gpio_probe_dt(struct platf
|
|
if (gpio == -EPROBE_DEFER)
|
|
return gpio;
|
|
/* ignore other errors as the pullup gpio is optional */
|
|
- pdata->ext_pullup_enable_pin = gpio;
|
|
+ pdata->ext_pullup_enable_pin = (gpio >= 0) ? gpio : -1;
|
|
|
|
pdev->dev.platform_data = pdata;
|
|
|
|
@@ -113,13 +140,15 @@ static int w1_gpio_probe_dt(struct platf
|
|
static int w1_gpio_probe(struct platform_device *pdev)
|
|
{
|
|
struct w1_bus_master *master;
|
|
- struct w1_gpio_platform_data *pdata;
|
|
+ struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
|
|
int err;
|
|
|
|
- if (of_have_populated_dt()) {
|
|
- err = w1_gpio_probe_dt(pdev);
|
|
- if (err < 0)
|
|
- return err;
|
|
+ if(pdata == NULL) {
|
|
+ if (of_have_populated_dt()) {
|
|
+ err = w1_gpio_probe_dt(pdev);
|
|
+ if (err < 0)
|
|
+ return err;
|
|
+ }
|
|
}
|
|
|
|
pdata = dev_get_platdata(&pdev->dev);
|
|
@@ -136,6 +165,22 @@ static int w1_gpio_probe(struct platform
|
|
return -ENOMEM;
|
|
}
|
|
|
|
+ w1_gpio_pin_orig = pdata->pin;
|
|
+ w1_gpio_pullup_pin_orig = pdata->ext_pullup_enable_pin;
|
|
+ w1_gpio_pullup_orig = pdata->parasitic_power;
|
|
+
|
|
+ if(gpio_is_valid(w1_gpio_pin)) {
|
|
+ pdata->pin = w1_gpio_pin;
|
|
+ pdata->ext_pullup_enable_pin = -1;
|
|
+ pdata->parasitic_power = -1;
|
|
+ }
|
|
+ pdata->parasitic_power |= w1_gpio_pullup;
|
|
+ if(gpio_is_valid(w1_gpio_pullup_pin)) {
|
|
+ pdata->ext_pullup_enable_pin = w1_gpio_pullup_pin;
|
|
+ }
|
|
+
|
|
+ dev_info(&pdev->dev, "gpio pin %d, external pullup pin %d, parasitic power %d\n", pdata->pin, pdata->ext_pullup_enable_pin, pdata->parasitic_power);
|
|
+
|
|
err = devm_gpio_request(&pdev->dev, pdata->pin, "w1");
|
|
if (err) {
|
|
dev_err(&pdev->dev, "gpio_request (pin) failed\n");
|
|
@@ -165,6 +210,14 @@ static int w1_gpio_probe(struct platform
|
|
master->set_pullup = w1_gpio_set_pullup;
|
|
}
|
|
|
|
+ if (pdata->parasitic_power) {
|
|
+ if (pdata->is_open_drain)
|
|
+ printk(KERN_ERR "w1-gpio 'pullup'(parasitic power) "
|
|
+ "option doesn't work with open drain GPIO\n");
|
|
+ else
|
|
+ master->bitbang_pullup = w1_gpio_bitbang_pullup;
|
|
+ }
|
|
+
|
|
err = w1_add_master_device(master);
|
|
if (err) {
|
|
dev_err(&pdev->dev, "w1_add_master device failed\n");
|
|
@@ -195,6 +248,10 @@ static int w1_gpio_remove(struct platfor
|
|
|
|
w1_remove_master_device(master);
|
|
|
|
+ pdata->pin = w1_gpio_pin_orig;
|
|
+ pdata->ext_pullup_enable_pin = w1_gpio_pullup_pin_orig;
|
|
+ pdata->parasitic_power = w1_gpio_pullup_orig;
|
|
+
|
|
return 0;
|
|
}
|
|
|
|
--- a/drivers/w1/w1.h
|
|
+++ b/drivers/w1/w1.h
|
|
@@ -171,6 +171,12 @@ struct w1_bus_master
|
|
|
|
u8 (*set_pullup)(void *, int);
|
|
|
|
+ /**
|
|
+ * Turns the pullup on/off in bitbanging mode, takes an on/off argument.
|
|
+ * @return -1=Error, 0=completed
|
|
+ */
|
|
+ void (*bitbang_pullup) (void *, u8);
|
|
+
|
|
void (*search)(void *, struct w1_master *,
|
|
u8, w1_slave_found_callback);
|
|
};
|
|
--- a/drivers/w1/w1_int.c
|
|
+++ b/drivers/w1/w1_int.c
|
|
@@ -123,6 +123,20 @@ int w1_add_master_device(struct w1_bus_m
|
|
return(-EINVAL);
|
|
}
|
|
|
|
+ /* bitbanging hardware uses bitbang_pullup, other hardware uses set_pullup
|
|
+ * and takes care of timing itself */
|
|
+ if (!master->write_byte && !master->touch_bit && master->set_pullup) {
|
|
+ printk(KERN_ERR "w1_add_master_device: set_pullup requires "
|
|
+ "write_byte or touch_bit, disabling\n");
|
|
+ master->set_pullup = NULL;
|
|
+ }
|
|
+
|
|
+ if (master->set_pullup && master->bitbang_pullup) {
|
|
+ printk(KERN_ERR "w1_add_master_device: set_pullup should not "
|
|
+ "be set when bitbang_pullup is used, disabling\n");
|
|
+ master->set_pullup = NULL;
|
|
+ }
|
|
+
|
|
/* Lock until the device is added (or not) to w1_masters. */
|
|
mutex_lock(&w1_mlock);
|
|
/* Search for the first available id (starting at 1). */
|
|
--- a/drivers/w1/w1_io.c
|
|
+++ b/drivers/w1/w1_io.c
|
|
@@ -134,10 +134,22 @@ static void w1_pre_write(struct w1_maste
|
|
static void w1_post_write(struct w1_master *dev)
|
|
{
|
|
if (dev->pullup_duration) {
|
|
- if (dev->enable_pullup && dev->bus_master->set_pullup)
|
|
- dev->bus_master->set_pullup(dev->bus_master->data, 0);
|
|
- else
|
|
+ if (dev->enable_pullup) {
|
|
+ if (dev->bus_master->set_pullup) {
|
|
+ dev->bus_master->set_pullup(dev->
|
|
+ bus_master->data,
|
|
+ 0);
|
|
+ } else if (dev->bus_master->bitbang_pullup) {
|
|
+ dev->bus_master->
|
|
+ bitbang_pullup(dev->bus_master->data, 1);
|
|
msleep(dev->pullup_duration);
|
|
+ dev->bus_master->
|
|
+ bitbang_pullup(dev->bus_master->data, 0);
|
|
+ }
|
|
+ } else {
|
|
+ msleep(dev->pullup_duration);
|
|
+ }
|
|
+
|
|
dev->pullup_duration = 0;
|
|
}
|
|
}
|
|
--- a/include/linux/w1-gpio.h
|
|
+++ b/include/linux/w1-gpio.h
|
|
@@ -18,6 +18,7 @@
|
|
struct w1_gpio_platform_data {
|
|
unsigned int pin;
|
|
unsigned int is_open_drain:1;
|
|
+ unsigned int parasitic_power:1;
|
|
void (*enable_external_pullup)(int enable);
|
|
unsigned int ext_pullup_enable_pin;
|
|
unsigned int pullup_duration;
|