linux/drivers/mfd/atmel-hlcdc.c
Boris Brezillon 2c2469bc03 mfd: atmel-hlcdc: Do not sleep in atomic context
readl_poll_timeout() calls usleep_range(), but
regmap_atmel_hlcdc_reg_write() is called in atomic context (regmap
spinlock held).

Replace the readl_poll_timeout() call by readl_poll_timeout_atomic().

Cc: <stable@vger.kernel.org>
Fixes: ea31c0cf9b ("mfd: atmel-hlcdc: Implement config synchronization")
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-10-04 15:48:04 +01:00

160 lines
4.1 KiB
C

/*
* Copyright (C) 2014 Free Electrons
* Copyright (C) 2014 Atmel
*
* Author: Boris BREZILLON <boris.brezillon@free-electrons.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.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk.h>
#include <linux/iopoll.h>
#include <linux/mfd/atmel-hlcdc.h>
#include <linux/mfd/core.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define ATMEL_HLCDC_REG_MAX (0x4000 - 0x4)
struct atmel_hlcdc_regmap {
void __iomem *regs;
};
static const struct mfd_cell atmel_hlcdc_cells[] = {
{
.name = "atmel-hlcdc-pwm",
.of_compatible = "atmel,hlcdc-pwm",
},
{
.name = "atmel-hlcdc-dc",
.of_compatible = "atmel,hlcdc-display-controller",
},
};
static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
unsigned int val)
{
struct atmel_hlcdc_regmap *hregmap = context;
if (reg <= ATMEL_HLCDC_DIS) {
u32 status;
readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
status, !(status & ATMEL_HLCDC_SIP),
1, 100);
}
writel(val, hregmap->regs + reg);
return 0;
}
static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
unsigned int *val)
{
struct atmel_hlcdc_regmap *hregmap = context;
*val = readl(hregmap->regs + reg);
return 0;
}
static const struct regmap_config atmel_hlcdc_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.max_register = ATMEL_HLCDC_REG_MAX,
.reg_write = regmap_atmel_hlcdc_reg_write,
.reg_read = regmap_atmel_hlcdc_reg_read,
.fast_io = true,
};
static int atmel_hlcdc_probe(struct platform_device *pdev)
{
struct atmel_hlcdc_regmap *hregmap;
struct device *dev = &pdev->dev;
struct atmel_hlcdc *hlcdc;
struct resource *res;
hregmap = devm_kzalloc(dev, sizeof(*hregmap), GFP_KERNEL);
if (!hregmap)
return -ENOMEM;
hlcdc = devm_kzalloc(dev, sizeof(*hlcdc), GFP_KERNEL);
if (!hlcdc)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
hregmap->regs = devm_ioremap_resource(dev, res);
if (IS_ERR(hregmap->regs))
return PTR_ERR(hregmap->regs);
hlcdc->irq = platform_get_irq(pdev, 0);
if (hlcdc->irq < 0)
return hlcdc->irq;
hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
if (IS_ERR(hlcdc->periph_clk)) {
dev_err(dev, "failed to get peripheral clock\n");
return PTR_ERR(hlcdc->periph_clk);
}
hlcdc->sys_clk = devm_clk_get(dev, "sys_clk");
if (IS_ERR(hlcdc->sys_clk)) {
dev_err(dev, "failed to get system clock\n");
return PTR_ERR(hlcdc->sys_clk);
}
hlcdc->slow_clk = devm_clk_get(dev, "slow_clk");
if (IS_ERR(hlcdc->slow_clk)) {
dev_err(dev, "failed to get slow clock\n");
return PTR_ERR(hlcdc->slow_clk);
}
hlcdc->regmap = devm_regmap_init(dev, NULL, hregmap,
&atmel_hlcdc_regmap_config);
if (IS_ERR(hlcdc->regmap))
return PTR_ERR(hlcdc->regmap);
dev_set_drvdata(dev, hlcdc);
return devm_mfd_add_devices(dev, -1, atmel_hlcdc_cells,
ARRAY_SIZE(atmel_hlcdc_cells),
NULL, 0, NULL);
}
static const struct of_device_id atmel_hlcdc_match[] = {
{ .compatible = "atmel,at91sam9n12-hlcdc" },
{ .compatible = "atmel,at91sam9x5-hlcdc" },
{ .compatible = "atmel,sama5d2-hlcdc" },
{ .compatible = "atmel,sama5d3-hlcdc" },
{ .compatible = "atmel,sama5d4-hlcdc" },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, atmel_hlcdc_match);
static struct platform_driver atmel_hlcdc_driver = {
.probe = atmel_hlcdc_probe,
.driver = {
.name = "atmel-hlcdc",
.of_match_table = atmel_hlcdc_match,
},
};
module_platform_driver(atmel_hlcdc_driver);
MODULE_ALIAS("platform:atmel-hlcdc");
MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
MODULE_DESCRIPTION("Atmel HLCDC driver");
MODULE_LICENSE("GPL v2");