1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Intel Low Power Subsystem PWM controller driver
4 *
5 * Copyright (C) 2014, Intel Corporation
6 *
7 * Derived from the original pwm-lpss.c
8 */
9
10 #include <linux/acpi.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_runtime.h>
15
16 #include "pwm-lpss.h"
17
18 /* BayTrail */
19 static const struct pwm_lpss_boardinfo pwm_lpss_byt_info = {
20 .clk_rate = 25000000,
21 .npwm = 1,
22 .base_unit_bits = 16,
23 };
24
25 /* Braswell */
26 static const struct pwm_lpss_boardinfo pwm_lpss_bsw_info = {
27 .clk_rate = 19200000,
28 .npwm = 1,
29 .base_unit_bits = 16,
30 .other_devices_aml_touches_pwm_regs = true,
31 };
32
33 /* Broxton */
34 static const struct pwm_lpss_boardinfo pwm_lpss_bxt_info = {
35 .clk_rate = 19200000,
36 .npwm = 4,
37 .base_unit_bits = 22,
38 .bypass = true,
39 };
40
pwm_lpss_probe_platform(struct platform_device * pdev)41 static int pwm_lpss_probe_platform(struct platform_device *pdev)
42 {
43 const struct pwm_lpss_boardinfo *info;
44 const struct acpi_device_id *id;
45 struct pwm_lpss_chip *lpwm;
46 struct resource *r;
47
48 id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
49 if (!id)
50 return -ENODEV;
51
52 info = (const struct pwm_lpss_boardinfo *)id->driver_data;
53 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
54
55 lpwm = pwm_lpss_probe(&pdev->dev, r, info);
56 if (IS_ERR(lpwm))
57 return PTR_ERR(lpwm);
58
59 platform_set_drvdata(pdev, lpwm);
60
61 dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_SMART_PREPARE);
62 pm_runtime_set_active(&pdev->dev);
63 pm_runtime_enable(&pdev->dev);
64
65 return 0;
66 }
67
pwm_lpss_remove_platform(struct platform_device * pdev)68 static int pwm_lpss_remove_platform(struct platform_device *pdev)
69 {
70 struct pwm_lpss_chip *lpwm = platform_get_drvdata(pdev);
71
72 pm_runtime_disable(&pdev->dev);
73 return pwm_lpss_remove(lpwm);
74 }
75
pwm_lpss_prepare(struct device * dev)76 static int pwm_lpss_prepare(struct device *dev)
77 {
78 struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev);
79
80 /*
81 * If other device's AML code touches the PWM regs on suspend/resume
82 * force runtime-resume the PWM controller to allow this.
83 */
84 if (lpwm->info->other_devices_aml_touches_pwm_regs)
85 return 0; /* Force runtime-resume */
86
87 return 1; /* If runtime-suspended leave as is */
88 }
89
90 static const struct dev_pm_ops pwm_lpss_platform_pm_ops = {
91 .prepare = pwm_lpss_prepare,
92 };
93
94 static const struct acpi_device_id pwm_lpss_acpi_match[] = {
95 { "80860F09", (unsigned long)&pwm_lpss_byt_info },
96 { "80862288", (unsigned long)&pwm_lpss_bsw_info },
97 { "80862289", (unsigned long)&pwm_lpss_bsw_info },
98 { "80865AC8", (unsigned long)&pwm_lpss_bxt_info },
99 { },
100 };
101 MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match);
102
103 static struct platform_driver pwm_lpss_driver_platform = {
104 .driver = {
105 .name = "pwm-lpss",
106 .acpi_match_table = pwm_lpss_acpi_match,
107 .pm = &pwm_lpss_platform_pm_ops,
108 },
109 .probe = pwm_lpss_probe_platform,
110 .remove = pwm_lpss_remove_platform,
111 };
112 module_platform_driver(pwm_lpss_driver_platform);
113
114 MODULE_DESCRIPTION("PWM platform driver for Intel LPSS");
115 MODULE_LICENSE("GPL v2");
116 MODULE_ALIAS("platform:pwm-lpss");
117