drivers/media/platform/s5p-mfc/s5p_mfc_pm.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * linux/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c
   4  *
   5  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   6  *              http://www.samsung.com/
   7  */
   8
   9 #include <linux/clk.h>
  10 #include <linux/err.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/pm_runtime.h>
  13 #include "s5p_mfc_common.h"
  14 #include "s5p_mfc_debug.h"
  15 #include "s5p_mfc_pm.h"
  16
  17 static struct s5p_mfc_pm *pm;
  18 static struct s5p_mfc_dev *p_dev;
  19 static atomic_t clk_ref;
  20
  21 int s5p_mfc_init_pm(struct s5p_mfc_dev *dev)
  22 {
  23         int i;
  24
  25         pm = &dev->pm;
  26         p_dev = dev;
  27
  28         pm->num_clocks = dev->variant->num_clocks;
  29         pm->clk_names = dev->variant->clk_names;
  30         pm->device = &dev->plat_dev->dev;
  31         pm->clock_gate = NULL;
  32
  33         /* clock control */
  34         for (i = 0; i < pm->num_clocks; i++) {
  35                 pm->clocks[i] = devm_clk_get(pm->device, pm->clk_names[i]);
  36                 if (IS_ERR(pm->clocks[i])) {
  37                         mfc_err("Failed to get clock: %s\n",
  38                                 pm->clk_names[i]);
  39                         return PTR_ERR(pm->clocks[i]);
  40                 }
  41         }
  42
  43         if (dev->variant->use_clock_gating)
  44                 pm->clock_gate = pm->clocks[0];
  45
  46         pm_runtime_enable(pm->device);
  47         atomic_set(&clk_ref, 0);
  48         return 0;
  49 }
  50
  51 void s5p_mfc_final_pm(struct s5p_mfc_dev *dev)
  52 {
  53         pm_runtime_disable(pm->device);
  54 }
  55
  56 int s5p_mfc_clock_on(void)
  57 {
  58         atomic_inc(&clk_ref);
  59         mfc_debug(3, "+ %d\n", atomic_read(&clk_ref));
  60
  61         return clk_enable(pm->clock_gate);
  62 }
  63
  64 void s5p_mfc_clock_off(void)
  65 {
  66         atomic_dec(&clk_ref);
  67         mfc_debug(3, "- %d\n", atomic_read(&clk_ref));
  68
  69         clk_disable(pm->clock_gate);
  70 }
  71
  72 int s5p_mfc_power_on(void)
  73 {
  74         int i, ret = 0;
  75
  76         ret = pm_runtime_get_sync(pm->device);
  77         if (ret < 0)
  78                 return ret;
  79
  80         /* clock control */
  81         for (i = 0; i < pm->num_clocks; i++) {
  82                 ret = clk_prepare_enable(pm->clocks[i]);
  83                 if (ret < 0) {
  84                         mfc_err("clock prepare failed for clock: %s\n",
  85                                 pm->clk_names[i]);
  86                         i++;
  87                         goto err;
  88                 }
  89         }
  90
  91         /* prepare for software clock gating */
  92         clk_disable(pm->clock_gate);
  93
  94         return 0;
  95 err:
  96         while (--i > 0)
  97                 clk_disable_unprepare(pm->clocks[i]);
  98         pm_runtime_put(pm->device);
  99         return ret;
 100 }
 101
 102 int s5p_mfc_power_off(void)
 103 {
 104         int i;
 105
 106         /* finish software clock gating */
 107         clk_enable(pm->clock_gate);
 108
 109         for (i = 0; i < pm->num_clocks; i++)
 110                 clk_disable_unprepare(pm->clocks[i]);
 111
 112         return pm_runtime_put_sync(pm->device);
 113 }
 114