1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | |
3 | #include <linux/component.h> |
4 | #include <linux/iopoll.h> |
5 | #include <linux/of.h> |
6 | #include <linux/platform_device.h> |
7 | |
8 | #include <drm/drm_bridge.h> |
9 | #include <drm/drm_mipi_dsi.h> |
10 | |
11 | #define DSI_GEN_HDR 0x6c |
12 | #define DSI_GEN_PLD_DATA 0x70 |
13 | |
14 | #define DSI_CMD_PKT_STATUS 0x74 |
15 | |
16 | #define GEN_PLD_R_EMPTY BIT(4) |
17 | #define GEN_PLD_W_FULL BIT(3) |
18 | #define GEN_PLD_W_EMPTY BIT(2) |
19 | #define GEN_CMD_FULL BIT(1) |
20 | #define GEN_CMD_EMPTY BIT(0) |
21 | #define GEN_RD_CMD_BUSY BIT(6) |
22 | #define CMD_PKT_STATUS_TIMEOUT_US 20000 |
23 | |
24 | struct adp_mipi_drv_private { |
25 | struct mipi_dsi_host dsi; |
26 | struct drm_bridge bridge; |
27 | struct drm_bridge *next_bridge; |
28 | void __iomem *mipi; |
29 | }; |
30 | |
31 | #define mipi_to_adp(x) container_of(x, struct adp_mipi_drv_private, dsi) |
32 | |
33 | static int adp_dsi_gen_pkt_hdr_write(struct adp_mipi_drv_private *adp, u32 hdr_val) |
34 | { |
35 | int ret; |
36 | u32 val, mask; |
37 | |
38 | ret = readl_poll_timeout(adp->mipi + DSI_CMD_PKT_STATUS, |
39 | val, !(val & GEN_CMD_FULL), 1000, |
40 | CMD_PKT_STATUS_TIMEOUT_US); |
41 | if (ret) { |
42 | dev_err(adp->dsi.dev, "failed to get available command FIFO\n" ); |
43 | return ret; |
44 | } |
45 | |
46 | writel(val: hdr_val, addr: adp->mipi + DSI_GEN_HDR); |
47 | |
48 | mask = GEN_CMD_EMPTY | GEN_PLD_W_EMPTY; |
49 | ret = readl_poll_timeout(adp->mipi + DSI_CMD_PKT_STATUS, |
50 | val, (val & mask) == mask, |
51 | 1000, CMD_PKT_STATUS_TIMEOUT_US); |
52 | if (ret) { |
53 | dev_err(adp->dsi.dev, "failed to write command FIFO\n" ); |
54 | return ret; |
55 | } |
56 | |
57 | return 0; |
58 | } |
59 | |
60 | static int adp_dsi_write(struct adp_mipi_drv_private *adp, |
61 | const struct mipi_dsi_packet *packet) |
62 | { |
63 | const u8 *tx_buf = packet->payload; |
64 | int len = packet->payload_length, pld_data_bytes = sizeof(u32), ret; |
65 | __le32 word; |
66 | u32 val; |
67 | |
68 | while (len) { |
69 | if (len < pld_data_bytes) { |
70 | word = 0; |
71 | memcpy(&word, tx_buf, len); |
72 | writel(le32_to_cpu(word), addr: adp->mipi + DSI_GEN_PLD_DATA); |
73 | len = 0; |
74 | } else { |
75 | memcpy(&word, tx_buf, pld_data_bytes); |
76 | writel(le32_to_cpu(word), addr: adp->mipi + DSI_GEN_PLD_DATA); |
77 | tx_buf += pld_data_bytes; |
78 | len -= pld_data_bytes; |
79 | } |
80 | |
81 | ret = readl_poll_timeout(adp->mipi + DSI_CMD_PKT_STATUS, |
82 | val, !(val & GEN_PLD_W_FULL), 1000, |
83 | CMD_PKT_STATUS_TIMEOUT_US); |
84 | if (ret) { |
85 | dev_err(adp->dsi.dev, |
86 | "failed to get available write payload FIFO\n" ); |
87 | return ret; |
88 | } |
89 | } |
90 | |
91 | word = 0; |
92 | memcpy(&word, packet->header, sizeof(packet->header)); |
93 | return adp_dsi_gen_pkt_hdr_write(adp, le32_to_cpu(word)); |
94 | } |
95 | |
96 | static int adp_dsi_read(struct adp_mipi_drv_private *adp, |
97 | const struct mipi_dsi_msg *msg) |
98 | { |
99 | int i, j, ret, len = msg->rx_len; |
100 | u8 *buf = msg->rx_buf; |
101 | u32 val; |
102 | |
103 | /* Wait end of the read operation */ |
104 | ret = readl_poll_timeout(adp->mipi + DSI_CMD_PKT_STATUS, |
105 | val, !(val & GEN_RD_CMD_BUSY), |
106 | 1000, CMD_PKT_STATUS_TIMEOUT_US); |
107 | if (ret) { |
108 | dev_err(adp->dsi.dev, "Timeout during read operation\n" ); |
109 | return ret; |
110 | } |
111 | |
112 | for (i = 0; i < len; i += 4) { |
113 | /* Read fifo must not be empty before all bytes are read */ |
114 | ret = readl_poll_timeout(adp->mipi + DSI_CMD_PKT_STATUS, |
115 | val, !(val & GEN_PLD_R_EMPTY), |
116 | 1000, CMD_PKT_STATUS_TIMEOUT_US); |
117 | if (ret) { |
118 | dev_err(adp->dsi.dev, "Read payload FIFO is empty\n" ); |
119 | return ret; |
120 | } |
121 | |
122 | val = readl(addr: adp->mipi + DSI_GEN_PLD_DATA); |
123 | for (j = 0; j < 4 && j + i < len; j++) |
124 | buf[i + j] = val >> (8 * j); |
125 | } |
126 | |
127 | return ret; |
128 | } |
129 | |
130 | static ssize_t adp_dsi_host_transfer(struct mipi_dsi_host *host, |
131 | const struct mipi_dsi_msg *msg) |
132 | { |
133 | struct adp_mipi_drv_private *adp = mipi_to_adp(host); |
134 | struct mipi_dsi_packet packet; |
135 | int ret, nb_bytes; |
136 | |
137 | ret = mipi_dsi_create_packet(packet: &packet, msg); |
138 | if (ret) { |
139 | dev_err(adp->dsi.dev, "failed to create packet: %d\n" , ret); |
140 | return ret; |
141 | } |
142 | |
143 | ret = adp_dsi_write(adp, packet: &packet); |
144 | if (ret) |
145 | return ret; |
146 | |
147 | if (msg->rx_buf && msg->rx_len) { |
148 | ret = adp_dsi_read(adp, msg); |
149 | if (ret) |
150 | return ret; |
151 | nb_bytes = msg->rx_len; |
152 | } else { |
153 | nb_bytes = packet.size; |
154 | } |
155 | |
156 | return nb_bytes; |
157 | } |
158 | |
159 | static int adp_dsi_bind(struct device *dev, struct device *master, void *data) |
160 | { |
161 | return 0; |
162 | } |
163 | |
164 | static void adp_dsi_unbind(struct device *dev, struct device *master, void *data) |
165 | { |
166 | } |
167 | |
168 | static const struct component_ops adp_dsi_component_ops = { |
169 | .bind = adp_dsi_bind, |
170 | .unbind = adp_dsi_unbind, |
171 | }; |
172 | |
173 | static int adp_dsi_host_attach(struct mipi_dsi_host *host, |
174 | struct mipi_dsi_device *dev) |
175 | { |
176 | struct adp_mipi_drv_private *adp = mipi_to_adp(host); |
177 | struct drm_bridge *next; |
178 | int ret; |
179 | |
180 | next = devm_drm_of_get_bridge(dev: adp->dsi.dev, node: adp->dsi.dev->of_node, port: 1, endpoint: 0); |
181 | if (IS_ERR(ptr: next)) |
182 | return PTR_ERR(ptr: next); |
183 | |
184 | adp->next_bridge = next; |
185 | |
186 | drm_bridge_add(bridge: &adp->bridge); |
187 | |
188 | ret = component_add(host->dev, &adp_dsi_component_ops); |
189 | if (ret) { |
190 | pr_err("failed to add dsi_host component: %d\n" , ret); |
191 | drm_bridge_remove(bridge: &adp->bridge); |
192 | return ret; |
193 | } |
194 | |
195 | return 0; |
196 | } |
197 | |
198 | static int adp_dsi_host_detach(struct mipi_dsi_host *host, |
199 | struct mipi_dsi_device *dev) |
200 | { |
201 | struct adp_mipi_drv_private *adp = mipi_to_adp(host); |
202 | |
203 | component_del(host->dev, &adp_dsi_component_ops); |
204 | drm_bridge_remove(bridge: &adp->bridge); |
205 | return 0; |
206 | } |
207 | |
208 | static const struct mipi_dsi_host_ops adp_dsi_host_ops = { |
209 | .transfer = adp_dsi_host_transfer, |
210 | .attach = adp_dsi_host_attach, |
211 | .detach = adp_dsi_host_detach, |
212 | }; |
213 | |
214 | static int adp_dsi_bridge_attach(struct drm_bridge *bridge, |
215 | struct drm_encoder *encoder, |
216 | enum drm_bridge_attach_flags flags) |
217 | { |
218 | struct adp_mipi_drv_private *adp = |
219 | container_of(bridge, struct adp_mipi_drv_private, bridge); |
220 | |
221 | return drm_bridge_attach(encoder, bridge: adp->next_bridge, previous: bridge, flags); |
222 | } |
223 | |
224 | static const struct drm_bridge_funcs adp_dsi_bridge_funcs = { |
225 | .attach = adp_dsi_bridge_attach, |
226 | }; |
227 | |
228 | static int adp_mipi_probe(struct platform_device *pdev) |
229 | { |
230 | struct adp_mipi_drv_private *adp; |
231 | |
232 | adp = devm_kzalloc(dev: &pdev->dev, size: sizeof(*adp), GFP_KERNEL); |
233 | if (!adp) |
234 | return -ENOMEM; |
235 | |
236 | adp->mipi = devm_platform_ioremap_resource(pdev, index: 0); |
237 | if (IS_ERR(ptr: adp->mipi)) { |
238 | dev_err(&pdev->dev, "failed to map mipi mmio" ); |
239 | return PTR_ERR(ptr: adp->mipi); |
240 | } |
241 | |
242 | adp->dsi.dev = &pdev->dev; |
243 | adp->dsi.ops = &adp_dsi_host_ops; |
244 | adp->bridge.funcs = &adp_dsi_bridge_funcs; |
245 | adp->bridge.of_node = pdev->dev.of_node; |
246 | adp->bridge.type = DRM_MODE_CONNECTOR_DSI; |
247 | dev_set_drvdata(dev: &pdev->dev, data: adp); |
248 | return mipi_dsi_host_register(host: &adp->dsi); |
249 | } |
250 | |
251 | static void adp_mipi_remove(struct platform_device *pdev) |
252 | { |
253 | struct device *dev = &pdev->dev; |
254 | struct adp_mipi_drv_private *adp = dev_get_drvdata(dev); |
255 | |
256 | mipi_dsi_host_unregister(host: &adp->dsi); |
257 | } |
258 | |
259 | static const struct of_device_id adp_mipi_of_match[] = { |
260 | { .compatible = "apple,h7-display-pipe-mipi" , }, |
261 | { }, |
262 | }; |
263 | MODULE_DEVICE_TABLE(of, adp_mipi_of_match); |
264 | |
265 | static struct platform_driver adp_mipi_platform_driver = { |
266 | .driver = { |
267 | .name = "adp-mipi" , |
268 | .of_match_table = adp_mipi_of_match, |
269 | }, |
270 | .probe = adp_mipi_probe, |
271 | .remove = adp_mipi_remove, |
272 | }; |
273 | |
274 | module_platform_driver(adp_mipi_platform_driver); |
275 | |
276 | MODULE_DESCRIPTION("Apple Display Pipe MIPI driver" ); |
277 | MODULE_LICENSE("GPL" ); |
278 | |