brcm2708: fix w1 patch
[openwrt/staging/wigyori.git] / target / linux / brcm2708 / patches-4.9 / 950-0058-enabling-the-realtime-clock-1-wire-chip-DS1307-and-1.patch
1 From 5edc95eee5ef69d7bfe03eede0e711e8f196dedc Mon Sep 17 00:00:00 2001
2 From: popcornmix <popcornmix@gmail.com>
3 Date: Wed, 8 May 2013 11:46:50 +0100
4 Subject: [PATCH] enabling the realtime clock 1-wire chip DS1307 and 1-wire on
5 GPIO4 (as a module)
6
7 1-wire: Add support for configuring pin for w1-gpio kernel module
8 See: https://github.com/raspberrypi/linux/pull/457
9
10 Add bitbanging pullups, use them for w1-gpio
11
12 Allows parasite power to work, uses module option pullup=1
13
14 bcm2708: Ensure 1-wire pullup is disabled by default, and expose as module parameter
15
16 Signed-off-by: Alex J Lennon <ajlennon@dynamicdevices.co.uk>
17
18 w1-gpio: Add gpiopin module parameter and correctly free up gpio pull-up pin, if set
19
20 Signed-off-by: Alex J Lennon <ajlennon@dynamicdevices.co.uk>
21
22 w1-gpio: Sort out the pullup/parasitic power tangle
23 ---
24 drivers/w1/masters/w1-gpio.c | 69 ++++++++++++++++++++++++++++++++++++++++----
25 drivers/w1/w1.h | 6 ++++
26 drivers/w1/w1_int.c | 14 +++++++++
27 drivers/w1/w1_io.c | 18 ++++++++++--
28 include/linux/w1-gpio.h | 1 +
29 5 files changed, 99 insertions(+), 9 deletions(-)
30
31 Index: linux-4.9.111/drivers/w1/masters/w1-gpio.c
32 ===================================================================
33 --- linux-4.9.111.orig/drivers/w1/masters/w1-gpio.c
34 +++ linux-4.9.111/drivers/w1/masters/w1-gpio.c
35 @@ -23,6 +23,19 @@
36 #include "../w1.h"
37 #include "../w1_int.h"
38
39 +static int w1_gpio_pullup = 0;
40 +static int w1_gpio_pullup_orig = 0;
41 +module_param_named(pullup, w1_gpio_pullup, int, 0);
42 +MODULE_PARM_DESC(pullup, "Enable parasitic power (power on data) mode");
43 +static int w1_gpio_pullup_pin = -1;
44 +static int w1_gpio_pullup_pin_orig = -1;
45 +module_param_named(extpullup, w1_gpio_pullup_pin, int, 0);
46 +MODULE_PARM_DESC(extpullup, "GPIO external pullup pin number");
47 +static int w1_gpio_pin = -1;
48 +static int w1_gpio_pin_orig = -1;
49 +module_param_named(gpiopin, w1_gpio_pin, int, 0);
50 +MODULE_PARM_DESC(gpiopin, "GPIO pin number");
51 +
52 static u8 w1_gpio_set_pullup(void *data, int delay)
53 {
54 struct w1_gpio_platform_data *pdata = data;
55 @@ -67,6 +80,16 @@ static u8 w1_gpio_read_bit(void *data)
56 return gpio_get_value(pdata->pin) ? 1 : 0;
57 }
58
59 +static void w1_gpio_bitbang_pullup(void *data, u8 on)
60 +{
61 + struct w1_gpio_platform_data *pdata = data;
62 +
63 + if (on)
64 + gpio_direction_output(pdata->pin, 1);
65 + else
66 + gpio_direction_input(pdata->pin);
67 +}
68 +
69 #if defined(CONFIG_OF)
70 static const struct of_device_id w1_gpio_dt_ids[] = {
71 { .compatible = "w1-gpio" },
72 @@ -80,6 +103,7 @@ static int w1_gpio_probe_dt(struct platf
73 struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
74 struct device_node *np = pdev->dev.of_node;
75 int gpio;
76 + u32 value;
77
78 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
79 if (!pdata)
80 @@ -88,6 +112,9 @@ static int w1_gpio_probe_dt(struct platf
81 if (of_get_property(np, "linux,open-drain", NULL))
82 pdata->is_open_drain = 1;
83
84 + if (of_property_read_u32(np, "rpi,parasitic-power", &value) == 0)
85 + pdata->parasitic_power = (value != 0);
86 +
87 gpio = of_get_gpio(np, 0);
88 if (gpio < 0) {
89 if (gpio != -EPROBE_DEFER)
90 @@ -103,7 +130,7 @@ static int w1_gpio_probe_dt(struct platf
91 if (gpio == -EPROBE_DEFER)
92 return gpio;
93 /* ignore other errors as the pullup gpio is optional */
94 - pdata->ext_pullup_enable_pin = gpio;
95 + pdata->ext_pullup_enable_pin = (gpio >= 0) ? gpio : -1;
96
97 pdev->dev.platform_data = pdata;
98
99 @@ -135,6 +162,22 @@ static int w1_gpio_probe(struct platform
100 return -ENOMEM;
101 }
102
103 + w1_gpio_pin_orig = pdata->pin;
104 + w1_gpio_pullup_pin_orig = pdata->ext_pullup_enable_pin;
105 + w1_gpio_pullup_orig = pdata->parasitic_power;
106 +
107 + if(gpio_is_valid(w1_gpio_pin)) {
108 + pdata->pin = w1_gpio_pin;
109 + pdata->ext_pullup_enable_pin = -1;
110 + pdata->parasitic_power = -1;
111 + }
112 + pdata->parasitic_power |= w1_gpio_pullup;
113 + if(gpio_is_valid(w1_gpio_pullup_pin)) {
114 + pdata->ext_pullup_enable_pin = w1_gpio_pullup_pin;
115 + }
116 +
117 + 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);
118 +
119 err = devm_gpio_request(&pdev->dev, pdata->pin, "w1");
120 if (err) {
121 dev_err(&pdev->dev, "gpio_request (pin) failed\n");
122 @@ -164,6 +207,14 @@ static int w1_gpio_probe(struct platform
123 master->set_pullup = w1_gpio_set_pullup;
124 }
125
126 + if (pdata->parasitic_power) {
127 + if (pdata->is_open_drain)
128 + printk(KERN_ERR "w1-gpio 'pullup'(parasitic power) "
129 + "option doesn't work with open drain GPIO\n");
130 + else
131 + master->bitbang_pullup = w1_gpio_bitbang_pullup;
132 + }
133 +
134 err = w1_add_master_device(master);
135 if (err) {
136 dev_err(&pdev->dev, "w1_add_master device failed\n");
137 @@ -194,6 +245,10 @@ static int w1_gpio_remove(struct platfor
138
139 w1_remove_master_device(master);
140
141 + pdata->pin = w1_gpio_pin_orig;
142 + pdata->ext_pullup_enable_pin = w1_gpio_pullup_pin_orig;
143 + pdata->parasitic_power = w1_gpio_pullup_orig;
144 +
145 return 0;
146 }
147
148 Index: linux-4.9.111/drivers/w1/w1.h
149 ===================================================================
150 --- linux-4.9.111.orig/drivers/w1/w1.h
151 +++ linux-4.9.111/drivers/w1/w1.h
152 @@ -173,6 +173,12 @@ struct w1_bus_master
153
154 u8 (*set_pullup)(void *, int);
155
156 + /**
157 + * Turns the pullup on/off in bitbanging mode, takes an on/off argument.
158 + * @return -1=Error, 0=completed
159 + */
160 + void (*bitbang_pullup) (void *, u8);
161 +
162 void (*search)(void *, struct w1_master *,
163 u8, w1_slave_found_callback);
164 };
165 Index: linux-4.9.111/drivers/w1/w1_int.c
166 ===================================================================
167 --- linux-4.9.111.orig/drivers/w1/w1_int.c
168 +++ linux-4.9.111/drivers/w1/w1_int.c
169 @@ -122,6 +122,20 @@ int w1_add_master_device(struct w1_bus_m
170 return(-EINVAL);
171 }
172
173 + /* bitbanging hardware uses bitbang_pullup, other hardware uses set_pullup
174 + * and takes care of timing itself */
175 + if (!master->write_byte && !master->touch_bit && master->set_pullup) {
176 + printk(KERN_ERR "w1_add_master_device: set_pullup requires "
177 + "write_byte or touch_bit, disabling\n");
178 + master->set_pullup = NULL;
179 + }
180 +
181 + if (master->set_pullup && master->bitbang_pullup) {
182 + printk(KERN_ERR "w1_add_master_device: set_pullup should not "
183 + "be set when bitbang_pullup is used, disabling\n");
184 + master->set_pullup = NULL;
185 + }
186 +
187 /* Lock until the device is added (or not) to w1_masters. */
188 mutex_lock(&w1_mlock);
189 /* Search for the first available id (starting at 1). */
190 Index: linux-4.9.111/drivers/w1/w1_io.c
191 ===================================================================
192 --- linux-4.9.111.orig/drivers/w1/w1_io.c
193 +++ linux-4.9.111/drivers/w1/w1_io.c
194 @@ -134,10 +134,22 @@ static void w1_pre_write(struct w1_maste
195 static void w1_post_write(struct w1_master *dev)
196 {
197 if (dev->pullup_duration) {
198 - if (dev->enable_pullup && dev->bus_master->set_pullup)
199 - dev->bus_master->set_pullup(dev->bus_master->data, 0);
200 - else
201 + if (dev->enable_pullup) {
202 + if (dev->bus_master->set_pullup) {
203 + dev->bus_master->set_pullup(dev->
204 + bus_master->data,
205 + 0);
206 + } else if (dev->bus_master->bitbang_pullup) {
207 + dev->bus_master->
208 + bitbang_pullup(dev->bus_master->data, 1);
209 msleep(dev->pullup_duration);
210 + dev->bus_master->
211 + bitbang_pullup(dev->bus_master->data, 0);
212 + }
213 + } else {
214 + msleep(dev->pullup_duration);
215 + }
216 +
217 dev->pullup_duration = 0;
218 }
219 }
220 Index: linux-4.9.111/include/linux/w1-gpio.h
221 ===================================================================
222 --- linux-4.9.111.orig/include/linux/w1-gpio.h
223 +++ linux-4.9.111/include/linux/w1-gpio.h
224 @@ -18,6 +18,7 @@
225 struct w1_gpio_platform_data {
226 unsigned int pin;
227 unsigned int is_open_drain:1;
228 + unsigned int parasitic_power:1;
229 void (*enable_external_pullup)(int enable);
230 unsigned int ext_pullup_enable_pin;
231 unsigned int pullup_duration;