1 /*
2  * Intel Low Power Subsystem PWM controller driver
3  *
4  * Copyright (C) 2014, Intel Corporation
5  *
6  * Derived from the original pwm-lpss.c
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/acpi.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_runtime.h>
18 
19 #include "pwm-lpss.h"
20 
21 /* BayTrail */
22 static const struct pwm_lpss_boardinfo pwm_lpss_byt_info = {
23 	.clk_rate = 25000000,
24 	.npwm = 1,
25 	.base_unit_bits = 16,
26 };
27 
28 /* Braswell */
29 static const struct pwm_lpss_boardinfo pwm_lpss_bsw_info = {
30 	.clk_rate = 19200000,
31 	.npwm = 1,
32 	.base_unit_bits = 16,
33 	.other_devices_aml_touches_pwm_regs = true,
34 };
35 
36 /* Broxton */
37 static const struct pwm_lpss_boardinfo pwm_lpss_bxt_info = {
38 	.clk_rate = 19200000,
39 	.npwm = 4,
40 	.base_unit_bits = 22,
41 	.bypass = true,
42 };
43 
44 static int pwm_lpss_probe_platform(struct platform_device *pdev)
45 {
46 	const struct pwm_lpss_boardinfo *info;
47 	const struct acpi_device_id *id;
48 	struct pwm_lpss_chip *lpwm;
49 	struct resource *r;
50 
51 	id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
52 	if (!id)
53 		return -ENODEV;
54 
55 	info = (const struct pwm_lpss_boardinfo *)id->driver_data;
56 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
57 
58 	lpwm = pwm_lpss_probe(&pdev->dev, r, info);
59 	if (IS_ERR(lpwm))
60 		return PTR_ERR(lpwm);
61 
62 	platform_set_drvdata(pdev, lpwm);
63 
64 	dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_SMART_PREPARE);
65 	pm_runtime_set_active(&pdev->dev);
66 	pm_runtime_enable(&pdev->dev);
67 
68 	return 0;
69 }
70 
71 static int pwm_lpss_remove_platform(struct platform_device *pdev)
72 {
73 	struct pwm_lpss_chip *lpwm = platform_get_drvdata(pdev);
74 
75 	pm_runtime_disable(&pdev->dev);
76 	return pwm_lpss_remove(lpwm);
77 }
78 
79 static int pwm_lpss_prepare(struct device *dev)
80 {
81 	struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev);
82 
83 	/*
84 	 * If other device's AML code touches the PWM regs on suspend/resume
85 	 * force runtime-resume the PWM controller to allow this.
86 	 */
87 	if (lpwm->info->other_devices_aml_touches_pwm_regs)
88 		return 0; /* Force runtime-resume */
89 
90 	return 1; /* If runtime-suspended leave as is */
91 }
92 
93 static const struct dev_pm_ops pwm_lpss_platform_pm_ops = {
94 	.prepare = pwm_lpss_prepare,
95 	SET_SYSTEM_SLEEP_PM_OPS(pwm_lpss_suspend, pwm_lpss_resume)
96 };
97 
98 static const struct acpi_device_id pwm_lpss_acpi_match[] = {
99 	{ "80860F09", (unsigned long)&pwm_lpss_byt_info },
100 	{ "80862288", (unsigned long)&pwm_lpss_bsw_info },
101 	{ "80862289", (unsigned long)&pwm_lpss_bsw_info },
102 	{ "80865AC8", (unsigned long)&pwm_lpss_bxt_info },
103 	{ },
104 };
105 MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match);
106 
107 static struct platform_driver pwm_lpss_driver_platform = {
108 	.driver = {
109 		.name = "pwm-lpss",
110 		.acpi_match_table = pwm_lpss_acpi_match,
111 		.pm = &pwm_lpss_platform_pm_ops,
112 	},
113 	.probe = pwm_lpss_probe_platform,
114 	.remove = pwm_lpss_remove_platform,
115 };
116 module_platform_driver(pwm_lpss_driver_platform);
117 
118 MODULE_DESCRIPTION("PWM platform driver for Intel LPSS");
119 MODULE_LICENSE("GPL v2");
120 MODULE_ALIAS("platform:pwm-lpss");
121