drivers/video/omap2/dss/sdi.c

   1 /*
   2  * linux/drivers/video/omap2/dss/sdi.c
   3  *
   4  * Copyright (C) 2009 Nokia Corporation
   5  * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 as published by
   9  * the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along with
  17  * this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #define DSS_SUBSYS_NAME "SDI"
  21
  22 #include <linux/kernel.h>
  23 #include <linux/delay.h>
  24 #include <linux/err.h>
  25 #include <linux/regulator/consumer.h>
  26 #include <linux/export.h>
  27 #include <linux/platform_device.h>
  28
  29 #include <video/omapdss.h>
  30 #include "dss.h"
  31
  32 static struct {
  33         bool update_enabled;
  34         struct regulator *vdds_sdi_reg;
  35
  36         struct dss_lcd_mgr_config mgr_config;
  37 } sdi;
  38
  39 static void sdi_config_lcd_manager(struct omap_dss_device *dssdev)
  40 {
  41         sdi.mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS;
  42
  43         sdi.mgr_config.stallmode = false;
  44         sdi.mgr_config.fifohandcheck = false;
  45
  46         sdi.mgr_config.video_port_width = 24;
  47         sdi.mgr_config.lcden_sig_polarity = 1;
  48
  49         dss_mgr_set_lcd_config(dssdev->manager, &sdi.mgr_config);
  50 }
  51
  52 int omapdss_sdi_display_enable(struct omap_dss_device *dssdev)
  53 {
  54         struct omap_video_timings *t = &dssdev->panel.timings;
  55         struct dss_clock_info dss_cinfo;
  56         struct dispc_clock_info dispc_cinfo;
  57         unsigned long pck;
  58         int r;
  59
  60         if (dssdev->manager == NULL) {
  61                 DSSERR("failed to enable display: no manager\n");
  62                 return -ENODEV;
  63         }
  64
  65         r = omap_dss_start_device(dssdev);
  66         if (r) {
  67                 DSSERR("failed to start device\n");
  68                 goto err_start_dev;
  69         }
  70
  71         r = regulator_enable(sdi.vdds_sdi_reg);
  72         if (r)
  73                 goto err_reg_enable;
  74
  75         r = dispc_runtime_get();
  76         if (r)
  77                 goto err_get_dispc;
  78
  79         /* 15.5.9.1.2 */
  80         dssdev->panel.timings.data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE;
  81         dssdev->panel.timings.sync_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE;
  82
  83         r = dss_calc_clock_div(t->pixel_clock * 1000, &dss_cinfo, &dispc_cinfo);
  84         if (r)
  85                 goto err_calc_clock_div;
  86
  87         sdi.mgr_config.clock_info = dispc_cinfo;
  88
  89         pck = dss_cinfo.fck / dispc_cinfo.lck_div / dispc_cinfo.pck_div / 1000;
  90
  91         if (pck != t->pixel_clock) {
  92                 DSSWARN("Could not find exact pixel clock. Requested %d kHz, "
  93                                 "got %lu kHz\n",
  94                                 t->pixel_clock, pck);
  95
  96                 t->pixel_clock = pck;
  97         }
  98
  99
 100         dss_mgr_set_timings(dssdev->manager, t);
 101
 102         r = dss_set_clock_div(&dss_cinfo);
 103         if (r)
 104                 goto err_set_dss_clock_div;
 105
 106         sdi_config_lcd_manager(dssdev);
 107
 108         /*
 109          * LCLK and PCLK divisors are located in shadow registers, and we
 110          * normally write them to DISPC registers when enabling the output.
 111          * However, SDI uses pck-free as source clock for its PLL, and pck-free
 112          * is affected by the divisors. And as we need the PLL before enabling
 113          * the output, we need to write the divisors early.
 114          *
 115          * It seems just writing to the DISPC register is enough, and we don't
 116          * need to care about the shadow register mechanism for pck-free. The
 117          * exact reason for this is unknown.
 118          */
 119         dispc_mgr_set_clock_div(dssdev->manager->id,
 120                         &sdi.mgr_config.clock_info);
 121
 122         dss_sdi_init(dssdev->phy.sdi.datapairs);
 123         r = dss_sdi_enable();
 124         if (r)
 125                 goto err_sdi_enable;
 126         mdelay(2);
 127
 128         r = dss_mgr_enable(dssdev->manager);
 129         if (r)
 130                 goto err_mgr_enable;
 131
 132         return 0;
 133
 134 err_mgr_enable:
 135         dss_sdi_disable();
 136 err_sdi_enable:
 137 err_set_dss_clock_div:
 138 err_calc_clock_div:
 139         dispc_runtime_put();
 140 err_get_dispc:
 141         regulator_disable(sdi.vdds_sdi_reg);
 142 err_reg_enable:
 143         omap_dss_stop_device(dssdev);
 144 err_start_dev:
 145         return r;
 146 }
 147 EXPORT_SYMBOL(omapdss_sdi_display_enable);
 148
 149 void omapdss_sdi_display_disable(struct omap_dss_device *dssdev)
 150 {
 151         dss_mgr_disable(dssdev->manager);
 152
 153         dss_sdi_disable();
 154
 155         dispc_runtime_put();
 156
 157         regulator_disable(sdi.vdds_sdi_reg);
 158
 159         omap_dss_stop_device(dssdev);
 160 }
 161 EXPORT_SYMBOL(omapdss_sdi_display_disable);
 162
 163 static int __init sdi_init_display(struct omap_dss_device *dssdev)
 164 {
 165         DSSDBG("SDI init\n");
 166
 167         if (sdi.vdds_sdi_reg == NULL) {
 168                 struct regulator *vdds_sdi;
 169
 170                 vdds_sdi = dss_get_vdds_sdi();
 171
 172                 if (IS_ERR(vdds_sdi)) {
 173                         DSSERR("can't get VDDS_SDI regulator\n");
 174                         return PTR_ERR(vdds_sdi);
 175                 }
 176
 177                 sdi.vdds_sdi_reg = vdds_sdi;
 178         }
 179
 180         return 0;
 181 }
 182
 183 static void __init sdi_probe_pdata(struct platform_device *pdev)
 184 {
 185         struct omap_dss_board_info *pdata = pdev->dev.platform_data;
 186         int i, r;
 187
 188         for (i = 0; i < pdata->num_devices; ++i) {
 189                 struct omap_dss_device *dssdev = pdata->devices[i];
 190
 191                 if (dssdev->type != OMAP_DISPLAY_TYPE_SDI)
 192                         continue;
 193
 194                 r = sdi_init_display(dssdev);
 195                 if (r) {
 196                         DSSERR("device %s init failed: %d\n", dssdev->name, r);
 197                         continue;
 198                 }
 199
 200                 r = omap_dss_register_device(dssdev, &pdev->dev, i);
 201                 if (r)
 202                         DSSERR("device %s register failed: %d\n",
 203                                         dssdev->name, r);
 204         }
 205 }
 206
 207 static int __init omap_sdi_probe(struct platform_device *pdev)
 208 {
 209         sdi_probe_pdata(pdev);
 210
 211         return 0;
 212 }
 213
 214 static int __exit omap_sdi_remove(struct platform_device *pdev)
 215 {
 216         omap_dss_unregister_child_devices(&pdev->dev);
 217
 218         return 0;
 219 }
 220
 221 static struct platform_driver omap_sdi_driver = {
 222         .remove         = __exit_p(omap_sdi_remove),
 223         .driver         = {
 224                 .name   = "omapdss_sdi",
 225                 .owner  = THIS_MODULE,
 226         },
 227 };
 228
 229 int __init sdi_init_platform_driver(void)
 230 {
 231         return platform_driver_probe(&omap_sdi_driver, omap_sdi_probe);
 232 }
 233
 234 void __exit sdi_uninit_platform_driver(void)
 235 {
 236         platform_driver_unregister(&omap_sdi_driver);
 237 }