linux/arch/arm/mach-u300/regulator.c
Wei Yongjun 1e74de30e0 ARM: u300: fix return value check in __u300_init_boardpower()
In case of error, the function syscon_node_to_regmap() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
2013-11-26 21:00:21 +01:00

134 lines
3.3 KiB
C

/*
* arch/arm/mach-u300/regulator.c
*
* Copyright (C) 2009 ST-Ericsson AB
* License terms: GNU General Public License (GPL) version 2
* Handle board-bound regulators and board power not related
* to any devices.
* Author: Linus Walleij <linus.walleij@stericsson.com>
*/
#include <linux/device.h>
#include <linux/signal.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/consumer.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
/* Power Management Control 16bit (R/W) */
#define U300_SYSCON_PMCR (0x50)
#define U300_SYSCON_PMCR_DCON_ENABLE (0x0002)
#define U300_SYSCON_PMCR_PWR_MGNT_ENABLE (0x0001)
/*
* Regulators that power the board and chip and which are
* not copuled to specific drivers are hogged in these
* instances.
*/
static struct regulator *main_power_15;
/*
* This function is used from pm.h to shut down the system by
* resetting all regulators in turn and then disable regulator
* LDO D (main power).
*/
void u300_pm_poweroff(void)
{
sigset_t old, all;
sigfillset(&all);
if (!sigprocmask(SIG_BLOCK, &all, &old)) {
/* Disable LDO D to shut down the system */
if (main_power_15)
regulator_disable(main_power_15);
else
pr_err("regulator not available to shut down system\n");
(void) sigprocmask(SIG_SETMASK, &old, NULL);
}
return;
}
/*
* Hog the regulators needed to power up the board.
*/
static int __init __u300_init_boardpower(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct device_node *syscon_np;
struct regmap *regmap;
int err;
pr_info("U300: setting up board power\n");
syscon_np = of_parse_phandle(np, "syscon", 0);
if (!syscon_np) {
pr_crit("U300: no syscon node\n");
return -ENODEV;
}
regmap = syscon_node_to_regmap(syscon_np);
if (IS_ERR(regmap)) {
pr_crit("U300: could not locate syscon regmap\n");
return PTR_ERR(regmap);
}
main_power_15 = regulator_get(&pdev->dev, "vana15");
if (IS_ERR(main_power_15)) {
pr_err("could not get vana15");
return PTR_ERR(main_power_15);
}
err = regulator_enable(main_power_15);
if (err) {
pr_err("could not enable vana15\n");
return err;
}
/*
* On U300 a special system controller register pulls up the DC
* until the vana15 (LDO D) regulator comes up. At this point, all
* regulators are set and we do not need power control via
* DC ON anymore. This function will likely be moved whenever
* the rest of the U300 power management is implemented.
*/
pr_info("U300: disable system controller pull-up\n");
regmap_update_bits(regmap, U300_SYSCON_PMCR,
U300_SYSCON_PMCR_DCON_ENABLE, 0);
/* Register globally exported PM poweroff hook */
pm_power_off = u300_pm_poweroff;
return 0;
}
static int __init s365_board_probe(struct platform_device *pdev)
{
return __u300_init_boardpower(pdev);
}
static const struct of_device_id s365_board_match[] = {
{ .compatible = "stericsson,s365" },
{},
};
static struct platform_driver s365_board_driver = {
.driver = {
.name = "s365-board",
.owner = THIS_MODULE,
.of_match_table = s365_board_match,
},
};
/*
* So at module init time we hog the regulator!
*/
static int __init u300_init_boardpower(void)
{
return platform_driver_probe(&s365_board_driver,
s365_board_probe);
}
device_initcall(u300_init_boardpower);