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195 lines · 5.0 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2013 NVIDIA Corporation
4 * Copyright (C) 2025 Svyatoslav Ryhel <[email protected]>
5 */
6
7#include <linux/clk.h>
8#include <linux/io.h>
9#include <linux/iopoll.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/of_platform.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <linux/tegra-mipi-cal.h>
16
17/* only need to support one provider */
18static struct {
19 struct device_node *np;
20 const struct tegra_mipi_ops *ops;
21} provider;
22
23/**
24 * tegra_mipi_enable - Enable the Tegra MIPI calibration device.
25 * @device: Handle to the Tegra MIPI calibration device.
26 *
27 * This calls the enable sequence for the Tegra MIPI calibration device.
28 *
29 * Returns 0 on success or a negative error code on failure.
30 */
31int tegra_mipi_enable(struct tegra_mipi_device *device)
32{
33 if (device->ops->enable)
34 return device->ops->enable(device);
35
36 return 0;
37}
38EXPORT_SYMBOL(tegra_mipi_enable);
39
40/**
41 * tegra_mipi_disable - Disable the Tegra MIPI calibration device.
42 * @device: Handle to the Tegra MIPI calibration device.
43 *
44 * This calls the disable sequence for the Tegra MIPI calibration device.
45 *
46 * Returns 0 on success or a negative error code on failure.
47 */
48int tegra_mipi_disable(struct tegra_mipi_device *device)
49{
50 if (device->ops->disable)
51 return device->ops->disable(device);
52
53 return 0;
54}
55EXPORT_SYMBOL(tegra_mipi_disable);
56
57/**
58 * tegra_mipi_start_calibration - Start the Tegra MIPI calibration sequence.
59 * @device: Handle to the Tegra MIPI calibration device.
60 *
61 * This initiates the calibration of CSI/DSI interfaces via the Tegra MIPI
62 * calibration device.
63 *
64 * Returns 0 on success or a negative error code on failure.
65 */
66int tegra_mipi_start_calibration(struct tegra_mipi_device *device)
67{
68 if (device->ops->start_calibration)
69 return device->ops->start_calibration(device);
70
71 return 0;
72}
73EXPORT_SYMBOL(tegra_mipi_start_calibration);
74
75/**
76 * tegra_mipi_finish_calibration - Finish the Tegra MIPI calibration sequence.
77 * @device: Handle to the Tegra MIPI calibration device.
78 *
79 * This completes the calibration of CSI/DSI interfaces via the Tegra MIPI
80 * calibration device.
81 *
82 * Returns 0 on success or a negative error code on failure.
83 */
84int tegra_mipi_finish_calibration(struct tegra_mipi_device *device)
85{
86 if (device->ops->finish_calibration)
87 return device->ops->finish_calibration(device);
88
89 return 0;
90}
91EXPORT_SYMBOL(tegra_mipi_finish_calibration);
92
93/**
94 * tegra_mipi_request - Request a Tegra MIPI calibration device.
95 * @device: Handle of the device requesting the MIPI calibration function.
96 * @np: Device node pointer of the device requesting the MIPI calibration
97 * function.
98 *
99 * This function requests a reference to a Tegra MIPI calibration device.
100 *
101 * Returns a pointer to the Tegra MIPI calibration device on success,
102 * or an ERR_PTR-encoded error code on failure.
103 */
104struct tegra_mipi_device *tegra_mipi_request(struct device *device,
105 struct device_node *np)
106{
107 struct tegra_mipi_device *mipidev;
108 struct of_phandle_args args;
109 int err;
110
111 err = of_parse_phandle_with_args(np, "nvidia,mipi-calibrate",
112 "#nvidia,mipi-calibrate-cells", 0,
113 &args);
114 if (err < 0)
115 return ERR_PTR(err);
116
117 if (provider.np != args.np) {
118 err = -ENODEV;
119 goto out;
120 }
121
122 mipidev = kzalloc_obj(*mipidev);
123 if (!mipidev) {
124 err = -ENOMEM;
125 goto out;
126 }
127
128 mipidev->pdev = of_find_device_by_node(args.np);
129 if (!mipidev->pdev) {
130 err = -ENODEV;
131 goto free;
132 }
133
134 of_node_put(args.np);
135
136 mipidev->ops = provider.ops;
137 mipidev->pads = args.args[0];
138
139 return mipidev;
140
141free:
142 kfree(mipidev);
143out:
144 of_node_put(args.np);
145 return ERR_PTR(err);
146}
147EXPORT_SYMBOL(tegra_mipi_request);
148
149/**
150 * tegra_mipi_free - Free a Tegra MIPI calibration device.
151 * @mipidev: Handle to the Tegra MIPI calibration device.
152 *
153 * This function releases a reference to a Tegra MIPI calibration device
154 * previously requested by tegra_mipi_request().
155 */
156void tegra_mipi_free(struct tegra_mipi_device *mipidev)
157{
158 platform_device_put(mipidev->pdev);
159 kfree(mipidev);
160}
161EXPORT_SYMBOL(tegra_mipi_free);
162
163static void tegra_mipi_remove_provider(void *data)
164{
165 provider.np = NULL;
166 provider.ops = NULL;
167}
168
169/**
170 * devm_tegra_mipi_add_provider - Managed registration of a Tegra MIPI
171 * calibration function provider.
172 * @device: Handle to the device providing the MIPI calibration function.
173 * @np: Device node pointer of the device providing the MIPI calibration
174 * function.
175 * @ops: Operations supported by the MIPI calibration device.
176 *
177 * This registers a device that provides MIPI calibration functions.
178 * For Tegra20 and Tegra30, this is the CSI block, while Tegra114 and
179 * newer SoC generations have a dedicated hardware block for these
180 * functions.
181 *
182 * Returns 0 on success or a negative error code on failure.
183 */
184int devm_tegra_mipi_add_provider(struct device *device, struct device_node *np,
185 const struct tegra_mipi_ops *ops)
186{
187 if (provider.np)
188 return -EBUSY;
189
190 provider.np = np;
191 provider.ops = ops;
192
193 return devm_add_action_or_reset(device, tegra_mipi_remove_provider, NULL);
194}
195EXPORT_SYMBOL(devm_tegra_mipi_add_provider);