drivers/gpu/drm/msm/dp/dp_clk_util.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Copyright (c) 2012-2015, 2017-2018, The Linux Foundation.
   3  * All rights reserved.
   4  */
   5
   6 #include <linux/clk.h>
   7 #include <linux/clk/clk-conf.h>
   8 #include <linux/err.h>
   9 #include <linux/delay.h>
  10 #include <linux/of.h>
  11
  12 #include <drm/drm_print.h>
  13
  14 #include "dp_clk_util.h"
  15
  16 void msm_dss_put_clk(struct dss_clk *clk_arry, int num_clk)
  17 {
  18         int i;
  19
  20         for (i = num_clk - 1; i >= 0; i--) {
  21                 if (clk_arry[i].clk)
  22                         clk_put(clk_arry[i].clk);
  23                 clk_arry[i].clk = NULL;
  24         }
  25 }
  26
  27 int msm_dss_get_clk(struct device *dev, struct dss_clk *clk_arry, int num_clk)
  28 {
  29         int i, rc = 0;
  30
  31         for (i = 0; i < num_clk; i++) {
  32                 clk_arry[i].clk = clk_get(dev, clk_arry[i].clk_name);
  33                 rc = PTR_ERR_OR_ZERO(clk_arry[i].clk);
  34                 if (rc) {
  35                         DEV_ERR("%pS->%s: '%s' get failed. rc=%d\n",
  36                                 __builtin_return_address(0), __func__,
  37                                 clk_arry[i].clk_name, rc);
  38                         goto error;
  39                 }
  40         }
  41
  42         return rc;
  43
  44 error:
  45         for (i--; i >= 0; i--) {
  46                 if (clk_arry[i].clk)
  47                         clk_put(clk_arry[i].clk);
  48                 clk_arry[i].clk = NULL;
  49         }
  50
  51         return rc;
  52 }
  53
  54 int msm_dss_clk_set_rate(struct dss_clk *clk_arry, int num_clk)
  55 {
  56         int i, rc = 0;
  57
  58         for (i = 0; i < num_clk; i++) {
  59                 if (clk_arry[i].clk) {
  60                         if (clk_arry[i].type != DSS_CLK_AHB) {
  61                                 DEV_DBG("%pS->%s: '%s' rate %ld\n",
  62                                         __builtin_return_address(0), __func__,
  63                                         clk_arry[i].clk_name,
  64                                         clk_arry[i].rate);
  65                                 rc = clk_set_rate(clk_arry[i].clk,
  66                                         clk_arry[i].rate);
  67                                 if (rc) {
  68                                         DEV_ERR("%pS->%s: %s failed. rc=%d\n",
  69                                                 __builtin_return_address(0),
  70                                                 __func__,
  71                                                 clk_arry[i].clk_name, rc);
  72                                         break;
  73                                 }
  74                         }
  75                 } else {
  76                         DEV_ERR("%pS->%s: '%s' is not available\n",
  77                                 __builtin_return_address(0), __func__,
  78                                 clk_arry[i].clk_name);
  79                         rc = -EPERM;
  80                         break;
  81                 }
  82         }
  83
  84         return rc;
  85 }
  86
  87 int msm_dss_enable_clk(struct dss_clk *clk_arry, int num_clk, int enable)
  88 {
  89         int i, rc = 0;
  90
  91         if (enable) {
  92                 for (i = 0; i < num_clk; i++) {
  93                         DEV_DBG("%pS->%s: enable '%s'\n",
  94                                 __builtin_return_address(0), __func__,
  95                                 clk_arry[i].clk_name);
  96                         rc = clk_prepare_enable(clk_arry[i].clk);
  97                         if (rc)
  98                                 DEV_ERR("%pS->%s: %s en fail. rc=%d\n",
  99                                         __builtin_return_address(0),
 100                                         __func__,
 101                                         clk_arry[i].clk_name, rc);
 102
 103                         if (rc && i) {
 104                                 msm_dss_enable_clk(&clk_arry[i - 1],
 105                                         i - 1, false);
 106                                 break;
 107                         }
 108                 }
 109         } else {
 110                 for (i = num_clk - 1; i >= 0; i--) {
 111                         DEV_DBG("%pS->%s: disable '%s'\n",
 112                                 __builtin_return_address(0), __func__,
 113                                 clk_arry[i].clk_name);
 114
 115                         clk_disable_unprepare(clk_arry[i].clk);
 116                 }
 117         }
 118
 119         return rc;
 120 }