linux_dsm_epyc7002/drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c
Wei Yongjun 5ec467a803 drm/rcar-du: Fix return value check in rcar_du_lvdsenc_get_resources()
In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR(). Also remove the dev_err call to avoid redundant
error message.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
[Remove the unneeded mem == NULL check]
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-12-18 11:10:48 +10:00

193 lines
4.7 KiB
C

/*
* rcar_du_lvdsenc.c -- R-Car Display Unit LVDS Encoder
*
* Copyright (C) 2013 Renesas Corporation
*
* Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "rcar_du_drv.h"
#include "rcar_du_encoder.h"
#include "rcar_du_lvdsenc.h"
#include "rcar_lvds_regs.h"
struct rcar_du_lvdsenc {
struct rcar_du_device *dev;
unsigned int index;
void __iomem *mmio;
struct clk *clock;
int dpms;
enum rcar_lvds_input input;
};
static void rcar_lvds_write(struct rcar_du_lvdsenc *lvds, u32 reg, u32 data)
{
iowrite32(data, lvds->mmio + reg);
}
static int rcar_du_lvdsenc_start(struct rcar_du_lvdsenc *lvds,
struct rcar_du_crtc *rcrtc)
{
const struct drm_display_mode *mode = &rcrtc->crtc.mode;
unsigned int freq = mode->clock;
u32 lvdcr0;
u32 lvdhcr;
u32 pllcr;
int ret;
if (lvds->dpms == DRM_MODE_DPMS_ON)
return 0;
ret = clk_prepare_enable(lvds->clock);
if (ret < 0)
return ret;
/* PLL clock configuration */
if (freq <= 38000)
pllcr = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_38M;
else if (freq <= 60000)
pllcr = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_60M;
else if (freq <= 121000)
pllcr = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_121M;
else
pllcr = LVDPLLCR_PLLDLYCNT_150M;
rcar_lvds_write(lvds, LVDPLLCR, pllcr);
/* Hardcode the channels and control signals routing for now.
*
* HSYNC -> CTRL0
* VSYNC -> CTRL1
* DISP -> CTRL2
* 0 -> CTRL3
*/
rcar_lvds_write(lvds, LVDCTRCR, LVDCTRCR_CTR3SEL_ZERO |
LVDCTRCR_CTR2SEL_DISP | LVDCTRCR_CTR1SEL_VSYNC |
LVDCTRCR_CTR0SEL_HSYNC);
if (rcar_du_needs(lvds->dev, RCAR_DU_QUIRK_LVDS_LANES))
lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 3)
| LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 1);
else
lvdhcr = LVDCHCR_CHSEL_CH(0, 0) | LVDCHCR_CHSEL_CH(1, 1)
| LVDCHCR_CHSEL_CH(2, 2) | LVDCHCR_CHSEL_CH(3, 3);
rcar_lvds_write(lvds, LVDCHCR, lvdhcr);
/* Select the input, hardcode mode 0, enable LVDS operation and turn
* bias circuitry on.
*/
lvdcr0 = LVDCR0_BEN | LVDCR0_LVEN;
if (rcrtc->index == 2)
lvdcr0 |= LVDCR0_DUSEL;
rcar_lvds_write(lvds, LVDCR0, lvdcr0);
/* Turn all the channels on. */
rcar_lvds_write(lvds, LVDCR1, LVDCR1_CHSTBY(3) | LVDCR1_CHSTBY(2) |
LVDCR1_CHSTBY(1) | LVDCR1_CHSTBY(0) | LVDCR1_CLKSTBY);
/* Turn the PLL on, wait for the startup delay, and turn the output
* on.
*/
lvdcr0 |= LVDCR0_PLLEN;
rcar_lvds_write(lvds, LVDCR0, lvdcr0);
usleep_range(100, 150);
lvdcr0 |= LVDCR0_LVRES;
rcar_lvds_write(lvds, LVDCR0, lvdcr0);
lvds->dpms = DRM_MODE_DPMS_ON;
return 0;
}
static void rcar_du_lvdsenc_stop(struct rcar_du_lvdsenc *lvds)
{
if (lvds->dpms == DRM_MODE_DPMS_OFF)
return;
rcar_lvds_write(lvds, LVDCR0, 0);
rcar_lvds_write(lvds, LVDCR1, 0);
clk_disable_unprepare(lvds->clock);
lvds->dpms = DRM_MODE_DPMS_OFF;
}
int rcar_du_lvdsenc_dpms(struct rcar_du_lvdsenc *lvds,
struct drm_crtc *crtc, int mode)
{
if (mode == DRM_MODE_DPMS_OFF) {
rcar_du_lvdsenc_stop(lvds);
return 0;
} else if (crtc) {
struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
return rcar_du_lvdsenc_start(lvds, rcrtc);
} else
return -EINVAL;
}
static int rcar_du_lvdsenc_get_resources(struct rcar_du_lvdsenc *lvds,
struct platform_device *pdev)
{
struct resource *mem;
char name[7];
sprintf(name, "lvds.%u", lvds->index);
mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
lvds->mmio = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(lvds->mmio))
return PTR_ERR(lvds->mmio);
lvds->clock = devm_clk_get(&pdev->dev, name);
if (IS_ERR(lvds->clock)) {
dev_err(&pdev->dev, "failed to get clock for %s\n", name);
return PTR_ERR(lvds->clock);
}
return 0;
}
int rcar_du_lvdsenc_init(struct rcar_du_device *rcdu)
{
struct platform_device *pdev = to_platform_device(rcdu->dev);
struct rcar_du_lvdsenc *lvds;
unsigned int i;
int ret;
for (i = 0; i < rcdu->info->num_lvds; ++i) {
lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
if (lvds == NULL) {
dev_err(&pdev->dev, "failed to allocate private data\n");
return -ENOMEM;
}
lvds->dev = rcdu;
lvds->index = i;
lvds->input = i ? RCAR_LVDS_INPUT_DU1 : RCAR_LVDS_INPUT_DU0;
lvds->dpms = DRM_MODE_DPMS_OFF;
ret = rcar_du_lvdsenc_get_resources(lvds, pdev);
if (ret < 0)
return ret;
rcdu->lvds[i] = lvds;
}
return 0;
}