diff options
Diffstat (limited to 'drivers/pwm')
-rw-r--r-- | drivers/pwm/Kconfig | 11 | ||||
-rw-r--r-- | drivers/pwm/Makefile | 1 | ||||
-rw-r--r-- | drivers/pwm/pwm-jz4740.c | 221 |
3 files changed, 232 insertions, 1 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index d954c72e242..e67800581d6 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig | |||
@@ -1,6 +1,5 @@ | |||
1 | menuconfig PWM | 1 | menuconfig PWM |
2 | bool "Pulse-Width Modulation (PWM) Support" | 2 | bool "Pulse-Width Modulation (PWM) Support" |
3 | depends on !MACH_JZ4740 | ||
4 | help | 3 | help |
5 | Generic Pulse-Width Modulation (PWM) support. | 4 | Generic Pulse-Width Modulation (PWM) support. |
6 | 5 | ||
@@ -56,6 +55,16 @@ config PWM_IMX | |||
56 | To compile this driver as a module, choose M here: the module | 55 | To compile this driver as a module, choose M here: the module |
57 | will be called pwm-imx. | 56 | will be called pwm-imx. |
58 | 57 | ||
58 | config PWM_JZ4740 | ||
59 | tristate "Ingenic JZ4740 PWM support" | ||
60 | depends on MACH_JZ4740 | ||
61 | help | ||
62 | Generic PWM framework driver for Ingenic JZ4740 based | ||
63 | machines. | ||
64 | |||
65 | To compile this driver as a module, choose M here: the module | ||
66 | will be called pwm-jz4740. | ||
67 | |||
59 | config PWM_LPC32XX | 68 | config PWM_LPC32XX |
60 | tristate "LPC32XX PWM support" | 69 | tristate "LPC32XX PWM support" |
61 | depends on ARCH_LPC32XX | 70 | depends on ARCH_LPC32XX |
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 360aad8fa3a..29cf57e2c25 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile | |||
@@ -2,6 +2,7 @@ obj-$(CONFIG_PWM) += core.o | |||
2 | obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o | 2 | obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o |
3 | obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o | 3 | obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o |
4 | obj-$(CONFIG_PWM_IMX) += pwm-imx.o | 4 | obj-$(CONFIG_PWM_IMX) += pwm-imx.o |
5 | obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o | ||
5 | obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o | 6 | obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o |
6 | obj-$(CONFIG_PWM_MXS) += pwm-mxs.o | 7 | obj-$(CONFIG_PWM_MXS) += pwm-mxs.o |
7 | obj-$(CONFIG_PWM_PUV3) += pwm-puv3.o | 8 | obj-$(CONFIG_PWM_PUV3) += pwm-puv3.o |
diff --git a/drivers/pwm/pwm-jz4740.c b/drivers/pwm/pwm-jz4740.c new file mode 100644 index 00000000000..10250fcefb9 --- /dev/null +++ b/drivers/pwm/pwm-jz4740.c | |||
@@ -0,0 +1,221 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de> | ||
3 | * JZ4740 platform PWM support | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or modify it | ||
6 | * under the terms of the GNU General Public License as published by the | ||
7 | * Free Software Foundation; either version 2 of the License, or (at your | ||
8 | * option) any later version. | ||
9 | * | ||
10 | * You should have received a copy of the GNU General Public License along | ||
11 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
12 | * 675 Mass Ave, Cambridge, MA 02139, USA. | ||
13 | * | ||
14 | */ | ||
15 | |||
16 | #include <linux/clk.h> | ||
17 | #include <linux/err.h> | ||
18 | #include <linux/gpio.h> | ||
19 | #include <linux/kernel.h> | ||
20 | #include <linux/module.h> | ||
21 | #include <linux/platform_device.h> | ||
22 | #include <linux/pwm.h> | ||
23 | |||
24 | #include <asm/mach-jz4740/gpio.h> | ||
25 | #include <asm/mach-jz4740/timer.h> | ||
26 | |||
27 | #define NUM_PWM 8 | ||
28 | |||
29 | static const unsigned int jz4740_pwm_gpio_list[NUM_PWM] = { | ||
30 | JZ_GPIO_PWM0, | ||
31 | JZ_GPIO_PWM1, | ||
32 | JZ_GPIO_PWM2, | ||
33 | JZ_GPIO_PWM3, | ||
34 | JZ_GPIO_PWM4, | ||
35 | JZ_GPIO_PWM5, | ||
36 | JZ_GPIO_PWM6, | ||
37 | JZ_GPIO_PWM7, | ||
38 | }; | ||
39 | |||
40 | struct jz4740_pwm_chip { | ||
41 | struct pwm_chip chip; | ||
42 | struct clk *clk; | ||
43 | }; | ||
44 | |||
45 | static inline struct jz4740_pwm_chip *to_jz4740(struct pwm_chip *chip) | ||
46 | { | ||
47 | return container_of(chip, struct jz4740_pwm_chip, chip); | ||
48 | } | ||
49 | |||
50 | static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) | ||
51 | { | ||
52 | unsigned int gpio = jz4740_pwm_gpio_list[pwm->hwpwm]; | ||
53 | int ret; | ||
54 | |||
55 | /* | ||
56 | * Timers 0 and 1 are used for system tasks, so they are unavailable | ||
57 | * for use as PWMs. | ||
58 | */ | ||
59 | if (pwm->hwpwm < 2) | ||
60 | return -EBUSY; | ||
61 | |||
62 | ret = gpio_request(gpio, pwm->label); | ||
63 | if (ret) { | ||
64 | dev_err(chip->dev, "Failed to request GPIO#%u for PWM: %d\n", | ||
65 | gpio, ret); | ||
66 | return ret; | ||
67 | } | ||
68 | |||
69 | jz_gpio_set_function(gpio, JZ_GPIO_FUNC_PWM); | ||
70 | |||
71 | jz4740_timer_start(pwm->hwpwm); | ||
72 | |||
73 | return 0; | ||
74 | } | ||
75 | |||
76 | static void jz4740_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) | ||
77 | { | ||
78 | unsigned int gpio = jz4740_pwm_gpio_list[pwm->hwpwm]; | ||
79 | |||
80 | jz4740_timer_set_ctrl(pwm->hwpwm, 0); | ||
81 | |||
82 | jz_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE); | ||
83 | gpio_free(gpio); | ||
84 | |||
85 | jz4740_timer_stop(pwm->hwpwm); | ||
86 | } | ||
87 | |||
88 | static int jz4740_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) | ||
89 | { | ||
90 | uint32_t ctrl = jz4740_timer_get_ctrl(pwm->pwm); | ||
91 | |||
92 | ctrl |= JZ_TIMER_CTRL_PWM_ENABLE; | ||
93 | jz4740_timer_set_ctrl(pwm->hwpwm, ctrl); | ||
94 | jz4740_timer_enable(pwm->hwpwm); | ||
95 | |||
96 | return 0; | ||
97 | } | ||
98 | |||
99 | static void jz4740_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) | ||
100 | { | ||
101 | uint32_t ctrl = jz4740_timer_get_ctrl(pwm->hwpwm); | ||
102 | |||
103 | ctrl &= ~JZ_TIMER_CTRL_PWM_ENABLE; | ||
104 | jz4740_timer_disable(pwm->hwpwm); | ||
105 | jz4740_timer_set_ctrl(pwm->hwpwm, ctrl); | ||
106 | } | ||
107 | |||
108 | static int jz4740_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, | ||
109 | int duty_ns, int period_ns) | ||
110 | { | ||
111 | struct jz4740_pwm_chip *jz4740 = to_jz4740(pwm->chip); | ||
112 | unsigned long long tmp; | ||
113 | unsigned long period, duty; | ||
114 | unsigned int prescaler = 0; | ||
115 | uint16_t ctrl; | ||
116 | bool is_enabled; | ||
117 | |||
118 | tmp = (unsigned long long)clk_get_rate(jz4740->clk) * period_ns; | ||
119 | do_div(tmp, 1000000000); | ||
120 | period = tmp; | ||
121 | |||
122 | while (period > 0xffff && prescaler < 6) { | ||
123 | period >>= 2; | ||
124 | ++prescaler; | ||
125 | } | ||
126 | |||
127 | if (prescaler == 6) | ||
128 | return -EINVAL; | ||
129 | |||
130 | tmp = (unsigned long long)period * duty_ns; | ||
131 | do_div(tmp, period_ns); | ||
132 | duty = period - tmp; | ||
133 | |||
134 | if (duty >= period) | ||
135 | duty = period - 1; | ||
136 | |||
137 | is_enabled = jz4740_timer_is_enabled(pwm->hwpwm); | ||
138 | if (is_enabled) | ||
139 | jz4740_pwm_disable(chip, pwm); | ||
140 | |||
141 | jz4740_timer_set_count(pwm->hwpwm, 0); | ||
142 | jz4740_timer_set_duty(pwm->hwpwm, duty); | ||
143 | jz4740_timer_set_period(pwm->hwpwm, period); | ||
144 | |||
145 | ctrl = JZ_TIMER_CTRL_PRESCALER(prescaler) | JZ_TIMER_CTRL_SRC_EXT | | ||
146 | JZ_TIMER_CTRL_PWM_ABBRUPT_SHUTDOWN; | ||
147 | |||
148 | jz4740_timer_set_ctrl(pwm->hwpwm, ctrl); | ||
149 | |||
150 | if (is_enabled) | ||
151 | jz4740_pwm_enable(chip, pwm); | ||
152 | |||
153 | return 0; | ||
154 | } | ||
155 | |||
156 | static const struct pwm_ops jz4740_pwm_ops = { | ||
157 | .request = jz4740_pwm_request, | ||
158 | .free = jz4740_pwm_free, | ||
159 | .config = jz4740_pwm_config, | ||
160 | .enable = jz4740_pwm_enable, | ||
161 | .disable = jz4740_pwm_disable, | ||
162 | .owner = THIS_MODULE, | ||
163 | }; | ||
164 | |||
165 | static int __devinit jz4740_pwm_probe(struct platform_device *pdev) | ||
166 | { | ||
167 | struct jz4740_pwm_chip *jz4740; | ||
168 | int ret; | ||
169 | |||
170 | jz4740 = devm_kzalloc(&pdev->dev, sizeof(*jz4740), GFP_KERNEL); | ||
171 | if (!jz4740) | ||
172 | return -ENOMEM; | ||
173 | |||
174 | jz4740->clk = clk_get(NULL, "ext"); | ||
175 | if (IS_ERR(jz4740->clk)) | ||
176 | return PTR_ERR(jz4740->clk); | ||
177 | |||
178 | jz4740->chip.dev = &pdev->dev; | ||
179 | jz4740->chip.ops = &jz4740_pwm_ops; | ||
180 | jz4740->chip.npwm = NUM_PWM; | ||
181 | jz4740->chip.base = -1; | ||
182 | |||
183 | ret = pwmchip_add(&jz4740->chip); | ||
184 | if (ret < 0) { | ||
185 | clk_put(jz4740->clk); | ||
186 | return ret; | ||
187 | } | ||
188 | |||
189 | platform_set_drvdata(pdev, jz4740); | ||
190 | |||
191 | return 0; | ||
192 | } | ||
193 | |||
194 | static int __devexit jz4740_pwm_remove(struct platform_device *pdev) | ||
195 | { | ||
196 | struct jz4740_pwm_chip *jz4740 = platform_get_drvdata(pdev); | ||
197 | int ret; | ||
198 | |||
199 | ret = pwmchip_remove(&jz4740->chip); | ||
200 | if (ret < 0) | ||
201 | return ret; | ||
202 | |||
203 | clk_put(jz4740->clk); | ||
204 | |||
205 | return 0; | ||
206 | } | ||
207 | |||
208 | static struct platform_driver jz4740_pwm_driver = { | ||
209 | .driver = { | ||
210 | .name = "jz4740-pwm", | ||
211 | .owner = THIS_MODULE, | ||
212 | }, | ||
213 | .probe = jz4740_pwm_probe, | ||
214 | .remove = __devexit_p(jz4740_pwm_remove), | ||
215 | }; | ||
216 | module_platform_driver(jz4740_pwm_driver); | ||
217 | |||
218 | MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); | ||
219 | MODULE_DESCRIPTION("Ingenic JZ4740 PWM driver"); | ||
220 | MODULE_ALIAS("platform:jz4740-pwm"); | ||
221 | MODULE_LICENSE("GPL"); | ||