xref: /linux/drivers/dpll/zl3073x/out.c (revision 53597deca0e38c30e6cd4ba2114fa42d2bcd85bb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/bitfield.h>
4 #include <linux/cleanup.h>
5 #include <linux/dev_printk.h>
6 #include <linux/string.h>
7 #include <linux/string_choices.h>
8 #include <linux/types.h>
9 
10 #include "core.h"
11 #include "out.h"
12 
13 /**
14  * zl3073x_out_state_fetch - fetch output state from hardware
15  * @zldev: pointer to zl3073x_dev structure
16  * @index: output index to fetch state for
17  *
18  * Function fetches state of the given output from hardware and stores it
19  * for later use.
20  *
21  * Return: 0 on success, <0 on error
22  */
23 int zl3073x_out_state_fetch(struct zl3073x_dev *zldev, u8 index)
24 {
25 	struct zl3073x_out *out = &zldev->out[index];
26 	int rc;
27 
28 	/* Read output configuration */
29 	rc = zl3073x_read_u8(zldev, ZL_REG_OUTPUT_CTRL(index), &out->ctrl);
30 	if (rc)
31 		return rc;
32 
33 	dev_dbg(zldev->dev, "OUT%u is %s and connected to SYNTH%u\n", index,
34 		str_enabled_disabled(zl3073x_out_is_enabled(out)),
35 		zl3073x_out_synth_get(out));
36 
37 	guard(mutex)(&zldev->multiop_lock);
38 
39 	/* Read output configuration */
40 	rc = zl3073x_mb_op(zldev, ZL_REG_OUTPUT_MB_SEM, ZL_OUTPUT_MB_SEM_RD,
41 			   ZL_REG_OUTPUT_MB_MASK, BIT(index));
42 	if (rc)
43 		return rc;
44 
45 	/* Read output mode */
46 	rc = zl3073x_read_u8(zldev, ZL_REG_OUTPUT_MODE, &out->mode);
47 	if (rc)
48 		return rc;
49 
50 	dev_dbg(zldev->dev, "OUT%u has signal format 0x%02x\n", index,
51 		zl3073x_out_signal_format_get(out));
52 
53 	/* Read output divisor */
54 	rc = zl3073x_read_u32(zldev, ZL_REG_OUTPUT_DIV, &out->div);
55 	if (rc)
56 		return rc;
57 
58 	if (!out->div) {
59 		dev_err(zldev->dev, "Zero divisor for OUT%u got from device\n",
60 			index);
61 		return -EINVAL;
62 	}
63 
64 	dev_dbg(zldev->dev, "OUT%u divisor: %u\n", index, out->div);
65 
66 	/* Read output width */
67 	rc = zl3073x_read_u32(zldev, ZL_REG_OUTPUT_WIDTH, &out->width);
68 	if (rc)
69 		return rc;
70 
71 	rc = zl3073x_read_u32(zldev, ZL_REG_OUTPUT_ESYNC_PERIOD,
72 			      &out->esync_n_period);
73 	if (rc)
74 		return rc;
75 
76 	if (!out->esync_n_period) {
77 		dev_err(zldev->dev,
78 			"Zero esync divisor for OUT%u got from device\n",
79 			index);
80 		return -EINVAL;
81 	}
82 
83 	rc = zl3073x_read_u32(zldev, ZL_REG_OUTPUT_ESYNC_WIDTH,
84 			      &out->esync_n_width);
85 	if (rc)
86 		return rc;
87 
88 	rc = zl3073x_read_u32(zldev, ZL_REG_OUTPUT_PHASE_COMP,
89 			      &out->phase_comp);
90 	if (rc)
91 		return rc;
92 
93 	return rc;
94 }
95 
96 /**
97  * zl3073x_out_state_get - get current output state
98  * @zldev: pointer to zl3073x_dev structure
99  * @index: output index to get state for
100  *
101  * Return: pointer to given output state
102  */
103 const struct zl3073x_out *zl3073x_out_state_get(struct zl3073x_dev *zldev,
104 						u8 index)
105 {
106 	return &zldev->out[index];
107 }
108 
109 /**
110  * zl3073x_out_state_set - commit output state changes to hardware
111  * @zldev: pointer to zl3073x_dev structure
112  * @index: output index to set state for
113  * @out: desired output state
114  *
115  * Validates that invariant fields have not been modified, skips the HW
116  * write if the mutable configuration is unchanged, and otherwise writes
117  * only the changed cfg fields to hardware via the mailbox interface.
118  *
119  * Return: 0 on success, -EINVAL if invariants changed, <0 on HW error
120  */
121 int zl3073x_out_state_set(struct zl3073x_dev *zldev, u8 index,
122 			  const struct zl3073x_out *out)
123 {
124 	struct zl3073x_out *dout = &zldev->out[index];
125 	int rc;
126 
127 	/* Reject attempts to change invariant fields (set at fetch only) */
128 	if (WARN_ON(memcmp(&dout->inv, &out->inv, sizeof(out->inv))))
129 		return -EINVAL;
130 
131 	/* Skip HW write if configuration hasn't changed */
132 	if (!memcmp(&dout->cfg, &out->cfg, sizeof(out->cfg)))
133 		return 0;
134 
135 	guard(mutex)(&zldev->multiop_lock);
136 
137 	/* Read output configuration into mailbox */
138 	rc = zl3073x_mb_op(zldev, ZL_REG_OUTPUT_MB_SEM, ZL_OUTPUT_MB_SEM_RD,
139 			   ZL_REG_OUTPUT_MB_MASK, BIT(index));
140 	if (rc)
141 		return rc;
142 
143 	/* Update mailbox with changed values */
144 	if (dout->div != out->div)
145 		rc = zl3073x_write_u32(zldev, ZL_REG_OUTPUT_DIV, out->div);
146 	if (!rc && dout->width != out->width)
147 		rc = zl3073x_write_u32(zldev, ZL_REG_OUTPUT_WIDTH, out->width);
148 	if (!rc && dout->esync_n_period != out->esync_n_period)
149 		rc = zl3073x_write_u32(zldev, ZL_REG_OUTPUT_ESYNC_PERIOD,
150 				       out->esync_n_period);
151 	if (!rc && dout->esync_n_width != out->esync_n_width)
152 		rc = zl3073x_write_u32(zldev, ZL_REG_OUTPUT_ESYNC_WIDTH,
153 				       out->esync_n_width);
154 	if (!rc && dout->mode != out->mode)
155 		rc = zl3073x_write_u8(zldev, ZL_REG_OUTPUT_MODE, out->mode);
156 	if (!rc && dout->phase_comp != out->phase_comp)
157 		rc = zl3073x_write_u32(zldev, ZL_REG_OUTPUT_PHASE_COMP,
158 				       out->phase_comp);
159 	if (rc)
160 		return rc;
161 
162 	/* Commit output configuration */
163 	rc = zl3073x_mb_op(zldev, ZL_REG_OUTPUT_MB_SEM, ZL_OUTPUT_MB_SEM_WR,
164 			   ZL_REG_OUTPUT_MB_MASK, BIT(index));
165 	if (rc)
166 		return rc;
167 
168 	/* After successful commit store new state */
169 	dout->cfg = out->cfg;
170 
171 	return 0;
172 }
173