1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Freescale ALSA SoC Machine driver utility
4 //
5 // Author: Timur Tabi <timur@freescale.com>
6 //
7 // Copyright 2010 Freescale Semiconductor, Inc.
8
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/module.h>
12 #include <linux/of_address.h>
13 #include <sound/soc.h>
14
15 #include "fsl_utils.h"
16
17 /**
18 * fsl_asoc_get_dma_channel - determine the dma channel for a SSI node
19 *
20 * @ssi_np: pointer to the SSI device tree node
21 * @name: name of the phandle pointing to the dma channel
22 * @dai: ASoC DAI link pointer to be filled with platform_name
23 * @dma_channel_id: dma channel id to be returned
24 * @dma_id: dma id to be returned
25 *
26 * This function determines the dma and channel id for given SSI node. It
27 * also discovers the platform_name for the ASoC DAI link.
28 */
29 int fsl_asoc_get_dma_channel(struct device_node *ssi_np,
30 const char *name,
31 struct snd_soc_dai_link *dai,
32 unsigned int *dma_channel_id,
33 unsigned int *dma_id)
34 {
35 struct resource res;
36 struct device_node *dma_channel_np, *dma_np;
37 const __be32 *iprop;
38 int ret;
39
40 dma_channel_np = of_parse_phandle(ssi_np, name, 0);
41 if (!dma_channel_np)
42 return -EINVAL;
43
44 if (!of_device_is_compatible(dma_channel_np, "fsl,ssi-dma-channel")) {
45 of_node_put(dma_channel_np);
46 return -EINVAL;
47 }
48
49 /* Determine the dev_name for the device_node. This code mimics the
50 * behavior of of_device_make_bus_id(). We need this because ASoC uses
51 * the dev_name() of the device to match the platform (DMA) device with
52 * the CPU (SSI) device. It's all ugly and hackish, but it works (for
53 * now).
54 *
55 * dai->platform name should already point to an allocated buffer.
56 */
57 ret = of_address_to_resource(dma_channel_np, 0, &res);
58 if (ret) {
59 of_node_put(dma_channel_np);
60 return ret;
61 }
62 snprintf((char *)dai->platforms->name, DAI_NAME_SIZE, "%llx.%pOFn",
63 (unsigned long long) res.start, dma_channel_np);
64
65 iprop = of_get_property(dma_channel_np, "cell-index", NULL);
66 if (!iprop) {
67 of_node_put(dma_channel_np);
68 return -EINVAL;
69 }
70 *dma_channel_id = be32_to_cpup(iprop);
71
72 dma_np = of_get_parent(dma_channel_np);
73 iprop = of_get_property(dma_np, "cell-index", NULL);
74 if (!iprop) {
75 of_node_put(dma_np);
76 of_node_put(dma_channel_np);
77 return -EINVAL;
78 }
79 *dma_id = be32_to_cpup(iprop);
80
81 of_node_put(dma_np);
82 of_node_put(dma_channel_np);
83
84 return 0;
85 }
86 EXPORT_SYMBOL(fsl_asoc_get_dma_channel);
87
88 /**
89 * fsl_asoc_get_pll_clocks - get two PLL clock source
90 *
91 * @dev: device pointer
92 * @pll8k_clk: PLL clock pointer for 8kHz
93 * @pll11k_clk: PLL clock pointer for 11kHz
94 *
95 * This function get two PLL clock source
96 */
97 void fsl_asoc_get_pll_clocks(struct device *dev, struct clk **pll8k_clk,
98 struct clk **pll11k_clk)
99 {
100 *pll8k_clk = devm_clk_get(dev, "pll8k");
101 if (IS_ERR(*pll8k_clk))
102 *pll8k_clk = NULL;
103
104 *pll11k_clk = devm_clk_get(dev, "pll11k");
105 if (IS_ERR(*pll11k_clk))
106 *pll11k_clk = NULL;
107 }
108 EXPORT_SYMBOL(fsl_asoc_get_pll_clocks);
109
110 /**
111 * fsl_asoc_reparent_pll_clocks - set clock parent if necessary
112 *
113 * @dev: device pointer
114 * @clk: root clock pointer
115 * @pll8k_clk: PLL clock pointer for 8kHz
116 * @pll11k_clk: PLL clock pointer for 11kHz
117 * @ratio: target requency for root clock
118 *
119 * This function set root clock parent according to the target ratio
120 */
121 void fsl_asoc_reparent_pll_clocks(struct device *dev, struct clk *clk,
122 struct clk *pll8k_clk,
123 struct clk *pll11k_clk, u64 ratio)
124 {
125 struct clk *p, *pll = NULL, *npll = NULL;
126 bool reparent = false;
127 int ret;
128
129 if (!clk || !pll8k_clk || !pll11k_clk)
130 return;
131
132 p = clk;
133 while (p && pll8k_clk && pll11k_clk) {
134 struct clk *pp = clk_get_parent(p);
135
136 if (clk_is_match(pp, pll8k_clk) ||
137 clk_is_match(pp, pll11k_clk)) {
138 pll = pp;
139 break;
140 }
141 p = pp;
142 }
143
144 npll = (do_div(ratio, 8000) ? pll11k_clk : pll8k_clk);
145 reparent = (pll && !clk_is_match(pll, npll));
146
147 if (reparent) {
148 ret = clk_set_parent(p, npll);
149 if (ret < 0)
150 dev_warn(dev, "failed to set parent:%d\n", ret);
151 }
152 }
153 EXPORT_SYMBOL(fsl_asoc_reparent_pll_clocks);
154
155 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
156 MODULE_DESCRIPTION("Freescale ASoC utility code");
157 MODULE_LICENSE("GPL v2");
158
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.