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Diffstat (limited to 'target/linux/brcm2708/patches-4.14/950-0058-enabling-the-realtime-clock-1-wire-chip-DS1307-and-1.patch')
-rw-r--r--target/linux/brcm2708/patches-4.14/950-0058-enabling-the-realtime-clock-1-wire-chip-DS1307-and-1.patch221
1 files changed, 221 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.14/950-0058-enabling-the-realtime-clock-1-wire-chip-DS1307-and-1.patch b/target/linux/brcm2708/patches-4.14/950-0058-enabling-the-realtime-clock-1-wire-chip-DS1307-and-1.patch
new file mode 100644
index 0000000000..d434102061
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.14/950-0058-enabling-the-realtime-clock-1-wire-chip-DS1307-and-1.patch
@@ -0,0 +1,221 @@
+From dc2d8a486db8a21cd998b0bdb117d30b8034aceb Mon Sep 17 00:00:00 2001
+From: popcornmix <popcornmix@gmail.com>
+Date: Wed, 8 May 2013 11:46:50 +0100
+Subject: [PATCH 058/454] 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
+---
+ drivers/w1/masters/w1-gpio.c | 69 ++++++++++++++++++++++++++++++++----
+ drivers/w1/w1_int.c | 14 ++++++++
+ drivers/w1/w1_io.c | 18 ++++++++--
+ include/linux/w1-gpio.h | 1 +
+ include/linux/w1.h | 6 ++++
+ 5 files changed, 99 insertions(+), 9 deletions(-)
+
+--- a/drivers/w1/masters/w1-gpio.c
++++ b/drivers/w1/masters/w1-gpio.c
+@@ -22,6 +22,19 @@
+
+ #include <linux/w1.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;
+@@ -66,6 +79,16 @@ 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" },
+@@ -79,6 +102,7 @@ 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)
+@@ -87,6 +111,9 @@ 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)
+@@ -102,7 +129,7 @@ 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;
+
+@@ -134,6 +161,22 @@ 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");
+@@ -163,6 +206,14 @@ 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");
+@@ -193,6 +244,10 @@ 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_int.c
++++ b/drivers/w1/w1_int.c
+@@ -114,6 +114,20 @@ 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
+@@ -126,10 +126,22 @@ 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;
+--- a/include/linux/w1.h
++++ b/include/linux/w1.h
+@@ -157,6 +157,12 @@ 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);
+ };