1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2009 Nokia Corporation
4 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
5 */
6
7#define DSS_SUBSYS_NAME "SDI"
8
9#include <linux/delay.h>
10#include <linux/err.h>
11#include <linux/export.h>
12#include <linux/kernel.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/regulator/consumer.h>
16#include <linux/string.h>
17
18#include <drm/drm_bridge.h>
19
20#include "dss.h"
21#include "omapdss.h"
22
23struct sdi_device {
24 struct platform_device *pdev;
25 struct dss_device *dss;
26
27 bool update_enabled;
28 struct regulator *vdds_sdi_reg;
29
30 struct dss_lcd_mgr_config mgr_config;
31 unsigned long pixelclock;
32 int datapairs;
33
34 struct omap_dss_device output;
35 struct drm_bridge bridge;
36};
37
38#define drm_bridge_to_sdi(bridge) \
39 container_of(bridge, struct sdi_device, bridge)
40
41struct sdi_clk_calc_ctx {
42 struct sdi_device *sdi;
43 unsigned long pck_min, pck_max;
44
45 unsigned long fck;
46 struct dispc_clock_info dispc_cinfo;
47};
48
49static bool dpi_calc_dispc_cb(int lckd, int pckd, unsigned long lck,
50 unsigned long pck, void *data)
51{
52 struct sdi_clk_calc_ctx *ctx = data;
53
54 ctx->dispc_cinfo.lck_div = lckd;
55 ctx->dispc_cinfo.pck_div = pckd;
56 ctx->dispc_cinfo.lck = lck;
57 ctx->dispc_cinfo.pck = pck;
58
59 return true;
60}
61
62static bool dpi_calc_dss_cb(unsigned long fck, void *data)
63{
64 struct sdi_clk_calc_ctx *ctx = data;
65
66 ctx->fck = fck;
67
68 return dispc_div_calc(dispc: ctx->sdi->dss->dispc, dispc_freq: fck,
69 pck_min: ctx->pck_min, pck_max: ctx->pck_max,
70 func: dpi_calc_dispc_cb, data: ctx);
71}
72
73static int sdi_calc_clock_div(struct sdi_device *sdi, unsigned long pclk,
74 unsigned long *fck,
75 struct dispc_clock_info *dispc_cinfo)
76{
77 int i;
78 struct sdi_clk_calc_ctx ctx;
79
80 /*
81 * DSS fclk gives us very few possibilities, so finding a good pixel
82 * clock may not be possible. We try multiple times to find the clock,
83 * each time widening the pixel clock range we look for, up to
84 * +/- 1MHz.
85 */
86
87 for (i = 0; i < 10; ++i) {
88 bool ok;
89
90 memset(&ctx, 0, sizeof(ctx));
91
92 ctx.sdi = sdi;
93
94 if (pclk > 1000 * i * i * i)
95 ctx.pck_min = max(pclk - 1000 * i * i * i, 0lu);
96 else
97 ctx.pck_min = 0;
98 ctx.pck_max = pclk + 1000 * i * i * i;
99
100 ok = dss_div_calc(dss: sdi->dss, pck: pclk, fck_min: ctx.pck_min,
101 func: dpi_calc_dss_cb, data: &ctx);
102 if (ok) {
103 *fck = ctx.fck;
104 *dispc_cinfo = ctx.dispc_cinfo;
105 return 0;
106 }
107 }
108
109 return -EINVAL;
110}
111
112static void sdi_config_lcd_manager(struct sdi_device *sdi)
113{
114 sdi->mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS;
115
116 sdi->mgr_config.stallmode = false;
117 sdi->mgr_config.fifohandcheck = false;
118
119 sdi->mgr_config.video_port_width = 24;
120 sdi->mgr_config.lcden_sig_polarity = 1;
121
122 dss_mgr_set_lcd_config(dssdev: &sdi->output, config: &sdi->mgr_config);
123}
124
125/* -----------------------------------------------------------------------------
126 * DRM Bridge Operations
127 */
128
129static int sdi_bridge_attach(struct drm_bridge *bridge,
130 enum drm_bridge_attach_flags flags)
131{
132 struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
133
134 if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
135 return -EINVAL;
136
137 return drm_bridge_attach(encoder: bridge->encoder, bridge: sdi->output.next_bridge,
138 previous: bridge, flags);
139}
140
141static enum drm_mode_status
142sdi_bridge_mode_valid(struct drm_bridge *bridge,
143 const struct drm_display_info *info,
144 const struct drm_display_mode *mode)
145{
146 struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
147 unsigned long pixelclock = mode->clock * 1000;
148 struct dispc_clock_info dispc_cinfo;
149 unsigned long fck;
150 int ret;
151
152 if (pixelclock == 0)
153 return MODE_NOCLOCK;
154
155 ret = sdi_calc_clock_div(sdi, pclk: pixelclock, fck: &fck, dispc_cinfo: &dispc_cinfo);
156 if (ret < 0)
157 return MODE_CLOCK_RANGE;
158
159 return MODE_OK;
160}
161
162static bool sdi_bridge_mode_fixup(struct drm_bridge *bridge,
163 const struct drm_display_mode *mode,
164 struct drm_display_mode *adjusted_mode)
165{
166 struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
167 unsigned long pixelclock = mode->clock * 1000;
168 struct dispc_clock_info dispc_cinfo;
169 unsigned long fck;
170 unsigned long pck;
171 int ret;
172
173 ret = sdi_calc_clock_div(sdi, pclk: pixelclock, fck: &fck, dispc_cinfo: &dispc_cinfo);
174 if (ret < 0)
175 return false;
176
177 pck = fck / dispc_cinfo.lck_div / dispc_cinfo.pck_div;
178
179 if (pck != pixelclock)
180 dev_dbg(&sdi->pdev->dev,
181 "pixel clock adjusted from %lu Hz to %lu Hz\n",
182 pixelclock, pck);
183
184 adjusted_mode->clock = pck / 1000;
185
186 return true;
187}
188
189static void sdi_bridge_mode_set(struct drm_bridge *bridge,
190 const struct drm_display_mode *mode,
191 const struct drm_display_mode *adjusted_mode)
192{
193 struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
194
195 sdi->pixelclock = adjusted_mode->clock * 1000;
196}
197
198static void sdi_bridge_enable(struct drm_bridge *bridge)
199{
200 struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
201 struct dispc_clock_info dispc_cinfo;
202 unsigned long fck;
203 int r;
204
205 r = regulator_enable(regulator: sdi->vdds_sdi_reg);
206 if (r)
207 return;
208
209 r = dispc_runtime_get(dispc: sdi->dss->dispc);
210 if (r)
211 goto err_get_dispc;
212
213 r = sdi_calc_clock_div(sdi, pclk: sdi->pixelclock, fck: &fck, dispc_cinfo: &dispc_cinfo);
214 if (r)
215 goto err_calc_clock_div;
216
217 sdi->mgr_config.clock_info = dispc_cinfo;
218
219 r = dss_set_fck_rate(dss: sdi->dss, rate: fck);
220 if (r)
221 goto err_set_dss_clock_div;
222
223 sdi_config_lcd_manager(sdi);
224
225 /*
226 * LCLK and PCLK divisors are located in shadow registers, and we
227 * normally write them to DISPC registers when enabling the output.
228 * However, SDI uses pck-free as source clock for its PLL, and pck-free
229 * is affected by the divisors. And as we need the PLL before enabling
230 * the output, we need to write the divisors early.
231 *
232 * It seems just writing to the DISPC register is enough, and we don't
233 * need to care about the shadow register mechanism for pck-free. The
234 * exact reason for this is unknown.
235 */
236 dispc_mgr_set_clock_div(dispc: sdi->dss->dispc, channel: sdi->output.dispc_channel,
237 cinfo: &sdi->mgr_config.clock_info);
238
239 dss_sdi_init(dss: sdi->dss, datapairs: sdi->datapairs);
240 r = dss_sdi_enable(dss: sdi->dss);
241 if (r)
242 goto err_sdi_enable;
243 mdelay(2);
244
245 r = dss_mgr_enable(dssdev: &sdi->output);
246 if (r)
247 goto err_mgr_enable;
248
249 return;
250
251err_mgr_enable:
252 dss_sdi_disable(dss: sdi->dss);
253err_sdi_enable:
254err_set_dss_clock_div:
255err_calc_clock_div:
256 dispc_runtime_put(dispc: sdi->dss->dispc);
257err_get_dispc:
258 regulator_disable(regulator: sdi->vdds_sdi_reg);
259}
260
261static void sdi_bridge_disable(struct drm_bridge *bridge)
262{
263 struct sdi_device *sdi = drm_bridge_to_sdi(bridge);
264
265 dss_mgr_disable(dssdev: &sdi->output);
266
267 dss_sdi_disable(dss: sdi->dss);
268
269 dispc_runtime_put(dispc: sdi->dss->dispc);
270
271 regulator_disable(regulator: sdi->vdds_sdi_reg);
272}
273
274static const struct drm_bridge_funcs sdi_bridge_funcs = {
275 .attach = sdi_bridge_attach,
276 .mode_valid = sdi_bridge_mode_valid,
277 .mode_fixup = sdi_bridge_mode_fixup,
278 .mode_set = sdi_bridge_mode_set,
279 .enable = sdi_bridge_enable,
280 .disable = sdi_bridge_disable,
281};
282
283static void sdi_bridge_init(struct sdi_device *sdi)
284{
285 sdi->bridge.funcs = &sdi_bridge_funcs;
286 sdi->bridge.of_node = sdi->pdev->dev.of_node;
287 sdi->bridge.type = DRM_MODE_CONNECTOR_LVDS;
288
289 drm_bridge_add(bridge: &sdi->bridge);
290}
291
292static void sdi_bridge_cleanup(struct sdi_device *sdi)
293{
294 drm_bridge_remove(bridge: &sdi->bridge);
295}
296
297/* -----------------------------------------------------------------------------
298 * Initialisation and Cleanup
299 */
300
301static int sdi_init_output(struct sdi_device *sdi)
302{
303 struct omap_dss_device *out = &sdi->output;
304 int r;
305
306 sdi_bridge_init(sdi);
307
308 out->dev = &sdi->pdev->dev;
309 out->id = OMAP_DSS_OUTPUT_SDI;
310 out->type = OMAP_DISPLAY_TYPE_SDI;
311 out->name = "sdi.0";
312 out->dispc_channel = OMAP_DSS_CHANNEL_LCD;
313 /* We have SDI only on OMAP3, where it's on port 1 */
314 out->of_port = 1;
315 out->bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE /* 15.5.9.1.2 */
316 | DRM_BUS_FLAG_SYNC_DRIVE_POSEDGE;
317
318 r = omapdss_device_init_output(out, local_bridge: &sdi->bridge);
319 if (r < 0) {
320 sdi_bridge_cleanup(sdi);
321 return r;
322 }
323
324 omapdss_device_register(dssdev: out);
325
326 return 0;
327}
328
329static void sdi_uninit_output(struct sdi_device *sdi)
330{
331 omapdss_device_unregister(dssdev: &sdi->output);
332 omapdss_device_cleanup_output(out: &sdi->output);
333
334 sdi_bridge_cleanup(sdi);
335}
336
337int sdi_init_port(struct dss_device *dss, struct platform_device *pdev,
338 struct device_node *port)
339{
340 struct sdi_device *sdi;
341 struct device_node *ep;
342 u32 datapairs;
343 int r;
344
345 sdi = kzalloc(size: sizeof(*sdi), GFP_KERNEL);
346 if (!sdi)
347 return -ENOMEM;
348
349 ep = of_get_next_child(node: port, NULL);
350 if (!ep) {
351 r = 0;
352 goto err_free;
353 }
354
355 r = of_property_read_u32(np: ep, propname: "datapairs", out_value: &datapairs);
356 of_node_put(node: ep);
357 if (r) {
358 DSSERR("failed to parse datapairs\n");
359 goto err_free;
360 }
361
362 sdi->datapairs = datapairs;
363 sdi->dss = dss;
364
365 sdi->pdev = pdev;
366 port->data = sdi;
367
368 sdi->vdds_sdi_reg = devm_regulator_get(dev: &pdev->dev, id: "vdds_sdi");
369 if (IS_ERR(ptr: sdi->vdds_sdi_reg)) {
370 r = PTR_ERR(ptr: sdi->vdds_sdi_reg);
371 if (r != -EPROBE_DEFER)
372 DSSERR("can't get VDDS_SDI regulator\n");
373 goto err_free;
374 }
375
376 r = sdi_init_output(sdi);
377 if (r)
378 goto err_free;
379
380 return 0;
381
382err_free:
383 kfree(objp: sdi);
384
385 return r;
386}
387
388void sdi_uninit_port(struct device_node *port)
389{
390 struct sdi_device *sdi = port->data;
391
392 if (!sdi)
393 return;
394
395 sdi_uninit_output(sdi);
396 kfree(objp: sdi);
397}
398

source code of linux/drivers/gpu/drm/omapdrm/dss/sdi.c