linux/drivers/clk/clk-oxnas.c
Wei Yongjun a5e9b85a65 clk: Fix return value check in oxnas_stdclk_probe()
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>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Fixes: 0bbd72b4c6 ("clk: Add Oxford Semiconductor OXNAS Standard Clocks")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-06-20 17:00:29 -07:00

196 lines
4.9 KiB
C

/*
* Copyright (C) 2010 Broadcom
* Copyright (C) 2012 Stephen Warren
* Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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-provider.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/stringify.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
/* Standard regmap gate clocks */
struct clk_oxnas {
struct clk_hw hw;
signed char bit;
struct regmap *regmap;
};
/* Regmap offsets */
#define CLK_STAT_REGOFFSET 0x24
#define CLK_SET_REGOFFSET 0x2c
#define CLK_CLR_REGOFFSET 0x30
static inline struct clk_oxnas *to_clk_oxnas(struct clk_hw *hw)
{
return container_of(hw, struct clk_oxnas, hw);
}
static int oxnas_clk_is_enabled(struct clk_hw *hw)
{
struct clk_oxnas *std = to_clk_oxnas(hw);
int ret;
unsigned int val;
ret = regmap_read(std->regmap, CLK_STAT_REGOFFSET, &val);
if (ret < 0)
return ret;
return val & BIT(std->bit);
}
static int oxnas_clk_enable(struct clk_hw *hw)
{
struct clk_oxnas *std = to_clk_oxnas(hw);
regmap_write(std->regmap, CLK_SET_REGOFFSET, BIT(std->bit));
return 0;
}
static void oxnas_clk_disable(struct clk_hw *hw)
{
struct clk_oxnas *std = to_clk_oxnas(hw);
regmap_write(std->regmap, CLK_CLR_REGOFFSET, BIT(std->bit));
}
static const struct clk_ops oxnas_clk_ops = {
.enable = oxnas_clk_enable,
.disable = oxnas_clk_disable,
.is_enabled = oxnas_clk_is_enabled,
};
static const char *const oxnas_clk_parents[] = {
"oscillator",
};
static const char *const eth_parents[] = {
"gmacclk",
};
#define DECLARE_STD_CLKP(__clk, __parent) \
static const struct clk_init_data clk_##__clk##_init = { \
.name = __stringify(__clk), \
.ops = &oxnas_clk_ops, \
.parent_names = __parent, \
.num_parents = ARRAY_SIZE(__parent), \
}
#define DECLARE_STD_CLK(__clk) DECLARE_STD_CLKP(__clk, oxnas_clk_parents)
/* Hardware Bit - Clock association */
struct clk_oxnas_init_data {
unsigned long bit;
const struct clk_init_data *clk_init;
};
/* Clk init data declaration */
DECLARE_STD_CLK(leon);
DECLARE_STD_CLK(dma_sgdma);
DECLARE_STD_CLK(cipher);
DECLARE_STD_CLK(sata);
DECLARE_STD_CLK(audio);
DECLARE_STD_CLK(usbmph);
DECLARE_STD_CLKP(etha, eth_parents);
DECLARE_STD_CLK(pciea);
DECLARE_STD_CLK(nand);
/* Table index is clock indice */
static const struct clk_oxnas_init_data clk_oxnas_init[] = {
[0] = {0, &clk_leon_init},
[1] = {1, &clk_dma_sgdma_init},
[2] = {2, &clk_cipher_init},
/* Skip & Do not touch to DDR clock */
[3] = {4, &clk_sata_init},
[4] = {5, &clk_audio_init},
[5] = {6, &clk_usbmph_init},
[6] = {7, &clk_etha_init},
[7] = {8, &clk_pciea_init},
[8] = {9, &clk_nand_init},
};
struct clk_oxnas_data {
struct clk_oxnas clk_oxnas[ARRAY_SIZE(clk_oxnas_init)];
struct clk_onecell_data onecell_data[ARRAY_SIZE(clk_oxnas_init)];
struct clk *clks[ARRAY_SIZE(clk_oxnas_init)];
};
static int oxnas_stdclk_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct clk_oxnas_data *clk_oxnas;
struct regmap *regmap;
int i;
clk_oxnas = devm_kzalloc(&pdev->dev, sizeof(*clk_oxnas), GFP_KERNEL);
if (!clk_oxnas)
return -ENOMEM;
regmap = syscon_node_to_regmap(of_get_parent(np));
if (IS_ERR(regmap)) {
dev_err(&pdev->dev, "failed to have parent regmap\n");
return PTR_ERR(regmap);
}
for (i = 0; i < ARRAY_SIZE(clk_oxnas_init); i++) {
struct clk_oxnas *_clk;
_clk = &clk_oxnas->clk_oxnas[i];
_clk->bit = clk_oxnas_init[i].bit;
_clk->hw.init = clk_oxnas_init[i].clk_init;
_clk->regmap = regmap;
clk_oxnas->clks[i] =
devm_clk_register(&pdev->dev, &_clk->hw);
if (WARN_ON(IS_ERR(clk_oxnas->clks[i])))
return PTR_ERR(clk_oxnas->clks[i]);
}
clk_oxnas->onecell_data->clks = clk_oxnas->clks;
clk_oxnas->onecell_data->clk_num = ARRAY_SIZE(clk_oxnas_init);
return of_clk_add_provider(np, of_clk_src_onecell_get,
clk_oxnas->onecell_data);
}
static int oxnas_stdclk_remove(struct platform_device *pdev)
{
of_clk_del_provider(pdev->dev.of_node);
return 0;
}
static const struct of_device_id oxnas_stdclk_dt_ids[] = {
{ .compatible = "oxsemi,ox810se-stdclk" },
{ }
};
MODULE_DEVICE_TABLE(of, oxnas_stdclk_dt_ids);
static struct platform_driver oxnas_stdclk_driver = {
.probe = oxnas_stdclk_probe,
.remove = oxnas_stdclk_remove,
.driver = {
.name = "oxnas-stdclk",
.of_match_table = oxnas_stdclk_dt_ids,
},
};
module_platform_driver(oxnas_stdclk_driver);