linux/drivers/phy/phy-exynos-mipi-video.c
Axel Lin af69decc7c phy: exynos-mipi-video: Use spin_lock to protct state->regmap rmw operations
The state->regmap is initialized by devm_regmap_init_mmio().
So it's fine to use spin_lock rather than mutex to protct state->regmap rmw
operations.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
[Julia.Lawall@lip6.fr: Found an issue with the original patch w.r.t unbalanced
 spin_lock call]
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2015-03-11 15:51:06 +05:30

197 lines
5.1 KiB
C

/*
* Samsung S5P/EXYNOS SoC series MIPI CSIS/DSIM DPHY driver
*
* Copyright (C) 2013 Samsung Electronics Co., Ltd.
* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon/exynos4-pmu.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/spinlock.h>
#include <linux/mfd/syscon.h>
/* MIPI_PHYn_CONTROL reg. offset (for base address from ioremap): n = 0..1 */
#define EXYNOS_MIPI_PHY_CONTROL(n) ((n) * 4)
enum exynos_mipi_phy_id {
EXYNOS_MIPI_PHY_ID_CSIS0,
EXYNOS_MIPI_PHY_ID_DSIM0,
EXYNOS_MIPI_PHY_ID_CSIS1,
EXYNOS_MIPI_PHY_ID_DSIM1,
EXYNOS_MIPI_PHYS_NUM
};
#define is_mipi_dsim_phy_id(id) \
((id) == EXYNOS_MIPI_PHY_ID_DSIM0 || (id) == EXYNOS_MIPI_PHY_ID_DSIM1)
struct exynos_mipi_video_phy {
struct video_phy_desc {
struct phy *phy;
unsigned int index;
} phys[EXYNOS_MIPI_PHYS_NUM];
spinlock_t slock;
void __iomem *regs;
struct regmap *regmap;
};
static int __set_phy_state(struct exynos_mipi_video_phy *state,
enum exynos_mipi_phy_id id, unsigned int on)
{
const unsigned int offset = EXYNOS4_MIPI_PHY_CONTROL(id / 2);
void __iomem *addr;
u32 val, reset;
if (is_mipi_dsim_phy_id(id))
reset = EXYNOS4_MIPI_PHY_MRESETN;
else
reset = EXYNOS4_MIPI_PHY_SRESETN;
spin_lock(&state->slock);
if (!IS_ERR(state->regmap)) {
regmap_read(state->regmap, offset, &val);
if (on)
val |= reset;
else
val &= ~reset;
regmap_write(state->regmap, offset, val);
if (on)
val |= EXYNOS4_MIPI_PHY_ENABLE;
else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
val &= ~EXYNOS4_MIPI_PHY_ENABLE;
regmap_write(state->regmap, offset, val);
} else {
addr = state->regs + EXYNOS_MIPI_PHY_CONTROL(id / 2);
val = readl(addr);
if (on)
val |= reset;
else
val &= ~reset;
writel(val, addr);
/* Clear ENABLE bit only if MRESETN, SRESETN bits are not set */
if (on)
val |= EXYNOS4_MIPI_PHY_ENABLE;
else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
val &= ~EXYNOS4_MIPI_PHY_ENABLE;
writel(val, addr);
}
spin_unlock(&state->slock);
return 0;
}
#define to_mipi_video_phy(desc) \
container_of((desc), struct exynos_mipi_video_phy, phys[(desc)->index]);
static int exynos_mipi_video_phy_power_on(struct phy *phy)
{
struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
return __set_phy_state(state, phy_desc->index, 1);
}
static int exynos_mipi_video_phy_power_off(struct phy *phy)
{
struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
return __set_phy_state(state, phy_desc->index, 0);
}
static struct phy *exynos_mipi_video_phy_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct exynos_mipi_video_phy *state = dev_get_drvdata(dev);
if (WARN_ON(args->args[0] >= EXYNOS_MIPI_PHYS_NUM))
return ERR_PTR(-ENODEV);
return state->phys[args->args[0]].phy;
}
static struct phy_ops exynos_mipi_video_phy_ops = {
.power_on = exynos_mipi_video_phy_power_on,
.power_off = exynos_mipi_video_phy_power_off,
.owner = THIS_MODULE,
};
static int exynos_mipi_video_phy_probe(struct platform_device *pdev)
{
struct exynos_mipi_video_phy *state;
struct device *dev = &pdev->dev;
struct phy_provider *phy_provider;
unsigned int i;
state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
if (!state)
return -ENOMEM;
state->regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon");
if (IS_ERR(state->regmap)) {
struct resource *res;
dev_info(dev, "regmap lookup failed: %ld\n",
PTR_ERR(state->regmap));
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
state->regs = devm_ioremap_resource(dev, res);
if (IS_ERR(state->regs))
return PTR_ERR(state->regs);
}
dev_set_drvdata(dev, state);
spin_lock_init(&state->slock);
for (i = 0; i < EXYNOS_MIPI_PHYS_NUM; i++) {
struct phy *phy = devm_phy_create(dev, NULL,
&exynos_mipi_video_phy_ops);
if (IS_ERR(phy)) {
dev_err(dev, "failed to create PHY %d\n", i);
return PTR_ERR(phy);
}
state->phys[i].phy = phy;
state->phys[i].index = i;
phy_set_drvdata(phy, &state->phys[i]);
}
phy_provider = devm_of_phy_provider_register(dev,
exynos_mipi_video_phy_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id exynos_mipi_video_phy_of_match[] = {
{ .compatible = "samsung,s5pv210-mipi-video-phy" },
{ },
};
MODULE_DEVICE_TABLE(of, exynos_mipi_video_phy_of_match);
static struct platform_driver exynos_mipi_video_phy_driver = {
.probe = exynos_mipi_video_phy_probe,
.driver = {
.of_match_table = exynos_mipi_video_phy_of_match,
.name = "exynos-mipi-video-phy",
}
};
module_platform_driver(exynos_mipi_video_phy_driver);
MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC MIPI CSI-2/DSI PHY driver");
MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
MODULE_LICENSE("GPL v2");