diff options
Diffstat (limited to 'target/linux/brcm2708/patches-3.18/0103-w1-gpio-Sort-out-the-pullup-parasitic-power-tangle.patch')
| -rwxr-xr-x | target/linux/brcm2708/patches-3.18/0103-w1-gpio-Sort-out-the-pullup-parasitic-power-tangle.patch | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-3.18/0103-w1-gpio-Sort-out-the-pullup-parasitic-power-tangle.patch b/target/linux/brcm2708/patches-3.18/0103-w1-gpio-Sort-out-the-pullup-parasitic-power-tangle.patch new file mode 100755 index 0000000000..614ad56a36 --- /dev/null +++ b/target/linux/brcm2708/patches-3.18/0103-w1-gpio-Sort-out-the-pullup-parasitic-power-tangle.patch @@ -0,0 +1,178 @@ +From 8ceb69e8548f27305e37866ec3b81a79e1402b1a Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.org> +Date: Wed, 4 Feb 2015 12:59:36 +0000 +Subject: [PATCH 103/114] w1-gpio: Sort out the pullup/parasitic power tangle + +--- + arch/arm/boot/dts/w1-gpio-overlay.dts | 4 +++- + arch/arm/boot/dts/w1-gpio-pullup-overlay.dts | 6 +++-- + drivers/w1/masters/w1-gpio.c | 36 ++++++++++++++++++---------- + include/linux/w1-gpio.h | 1 + + 4 files changed, 32 insertions(+), 15 deletions(-) + +diff --git a/arch/arm/boot/dts/w1-gpio-overlay.dts b/arch/arm/boot/dts/w1-gpio-overlay.dts +index b2c5ee2..29a3b48 100644 +--- a/arch/arm/boot/dts/w1-gpio-overlay.dts ++++ b/arch/arm/boot/dts/w1-gpio-overlay.dts +@@ -1,4 +1,4 @@ +-// Definitions for lirc-rpi module ++// Definitions for w1-gpio module (without external pullup) + /dts-v1/; + /plugin/; + +@@ -14,6 +14,7 @@ + pinctrl-names = "default"; + pinctrl-0 = <&w1_pins>; + gpios = <&gpio 4 0>; ++ rpi,parasitic-power = <0>; + status = "okay"; + }; + }; +@@ -33,5 +34,6 @@ + __overrides__ { + gpiopin = <&w1>,"gpios:4", + <&w1_pins>,"brcm,pins:0"; ++ pullup = <&w1>,"rpi,parasitic-power:0"; + }; + }; +diff --git a/arch/arm/boot/dts/w1-gpio-pullup-overlay.dts b/arch/arm/boot/dts/w1-gpio-pullup-overlay.dts +index b3e97c2..66a98f6 100644 +--- a/arch/arm/boot/dts/w1-gpio-pullup-overlay.dts ++++ b/arch/arm/boot/dts/w1-gpio-pullup-overlay.dts +@@ -1,4 +1,4 @@ +-// Definitions for lirc-rpi module ++// Definitions for w1-gpio module (with external pullup) + /dts-v1/; + /plugin/; + +@@ -14,6 +14,7 @@ + pinctrl-names = "default"; + pinctrl-0 = <&w1_pins>; + gpios = <&gpio 4 0>, <&gpio 5 1>; ++ rpi,parasitic-power = <0>; + status = "okay"; + }; + }; +@@ -33,7 +34,8 @@ + __overrides__ { + gpiopin = <&w1>,"gpios:4", + <&w1_pins>,"brcm,pins:0"; +- pullup = <&w1>,"gpios:16", ++ extpullup = <&w1>,"gpios:16", + <&w1_pins>,"brcm,pins:4"; ++ pullup = <&w1>,"rpi,parasitic-power:0"; + }; + }; +diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c +index 61be2cd..54c0313 100644 +--- a/drivers/w1/masters/w1-gpio.c ++++ b/drivers/w1/masters/w1-gpio.c +@@ -23,10 +23,14 @@ + #include "../w1.h" + #include "../w1_int.h" + +-static int w1_gpio_pullup = -1; +-static int w1_gpio_pullup_orig = -1; ++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, "GPIO pin pullup number"); ++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); +@@ -99,6 +103,7 @@ static int w1_gpio_probe_dt(struct platform_device *pdev) + 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) +@@ -107,6 +112,9 @@ static int w1_gpio_probe_dt(struct platform_device *pdev) + 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) +@@ -122,7 +130,7 @@ static int w1_gpio_probe_dt(struct platform_device *pdev) + 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; + +@@ -158,17 +166,20 @@ static int w1_gpio_probe(struct platform_device *pdev) + } + + w1_gpio_pin_orig = pdata->pin; +- w1_gpio_pullup_orig = pdata->ext_pullup_enable_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; + } +- if(gpio_is_valid(w1_gpio_pullup)) { +- pdata->ext_pullup_enable_pin = w1_gpio_pullup; ++ 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, gpio pullup pin %d\n", pdata->pin, pdata->ext_pullup_enable_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) { +@@ -199,10 +210,10 @@ static int w1_gpio_probe(struct platform_device *pdev) + master->set_pullup = w1_gpio_set_pullup; + } + +- if (gpio_is_valid(w1_gpio_pullup)) { ++ if (pdata->parasitic_power) { + if (pdata->is_open_drain) +- printk(KERN_ERR "w1-gpio 'pullup' option " +- "doesn't work with open drain GPIO\n"); ++ 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; + } +@@ -238,7 +249,8 @@ static int w1_gpio_remove(struct platform_device *pdev) + w1_remove_master_device(master); + + pdata->pin = w1_gpio_pin_orig; +- pdata->ext_pullup_enable_pin = w1_gpio_pullup_orig; ++ pdata->ext_pullup_enable_pin = w1_gpio_pullup_pin_orig; ++ pdata->parasitic_power = w1_gpio_pullup_orig; + + return 0; + } +diff --git a/include/linux/w1-gpio.h b/include/linux/w1-gpio.h +index d58594a..feae942 100644 +--- 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; +-- +1.8.3.2 + |