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Diffstat (limited to 'drivers/mfd/syscon.c')
-rw-r--r--drivers/mfd/syscon.c146
1 files changed, 83 insertions, 63 deletions
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 8099419378..3c2e1241fd 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -1,14 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/* System Control Driver
*
* Based on linux driver by:
* Copyright (C) 2012 Freescale Semiconductor, Inc.
* Copyright (C) 2012 Linaro Ltd.
* Author: Dong Aisheng <dong.aisheng@linaro.org>
- *
- * 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 <io.h>
@@ -19,6 +15,8 @@
#include <xfuncs.h>
#include <of_address.h>
#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/regmap.h>
#include <mfd/syscon.h>
@@ -31,42 +29,20 @@ struct syscon {
struct regmap *regmap;
};
-static int syscon_reg_write(void *context, unsigned int reg,
- unsigned int val)
-{
- struct syscon *syscon = context;
- writel(val, syscon->base + reg);
- return 0;
-}
-
-static int syscon_reg_read(void *context, unsigned int reg,
- unsigned int *val)
-{
- struct syscon *syscon = context;
- *val = readl(syscon->base + reg);
- return 0;
-}
-
-static const struct regmap_bus syscon_regmap_bus = {
- .reg_write = syscon_reg_write,
- .reg_read = syscon_reg_read,
-};
-
static const struct regmap_config syscon_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
};
-static struct syscon *of_syscon_register(struct device_node *np)
+static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
{
- int ret;
+ struct regmap_config syscon_config = syscon_regmap_config;
struct syscon *syscon;
+ u32 reg_io_width;
+ int ret;
struct resource res;
- if (!of_device_is_compatible(np, "syscon"))
- return ERR_PTR(-EINVAL);
-
syscon = xzalloc(sizeof(*syscon));
if (of_address_to_resource(np, 0, &res)) {
@@ -75,14 +51,48 @@ static struct syscon *of_syscon_register(struct device_node *np)
}
syscon->base = IOMEM(res.start);
- syscon->np = np;
+
+ /* Parse the device's DT node for an endianness specification */
+ if (of_property_read_bool(np, "big-endian"))
+ syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
+ else if (of_property_read_bool(np, "little-endian"))
+ syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
+ else if (of_property_read_bool(np, "native-endian"))
+ syscon_config.val_format_endian = REGMAP_ENDIAN_NATIVE;
+
+ /*
+ * search for reg-io-width property in DT. If it is not provided,
+ * default to 4 bytes. regmap_init_mmio will return an error if values
+ * are invalid so there is no need to check them here.
+ */
+ ret = of_property_read_u32(np, "reg-io-width", &reg_io_width);
+ if (ret)
+ reg_io_width = 4;
+
+ syscon_config.name = np->full_name;
+ syscon_config.reg_stride = reg_io_width;
+ syscon_config.val_bits = reg_io_width * 8;
+ syscon_config.max_register = resource_size(&res) - reg_io_width;
+
+ syscon->regmap = regmap_init_mmio_clk(NULL, NULL, syscon->base,
+ &syscon_config);
+
+ if (check_clk) {
+ struct clk *clk = of_clk_get(np, 0);
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ /* clock is optional */
+ if (ret != -ENOENT)
+ goto err_map;
+ } else {
+ ret = regmap_mmio_attach_clk(syscon->regmap, clk);
+ if (ret)
+ goto err_map;
+ }
+ }
list_add_tail(&syscon->list, &syscon_list);
- syscon->regmap = regmap_init(NULL,
- &syscon_regmap_bus,
- syscon,
- &syscon_regmap_config);
return syscon;
err_map:
@@ -90,7 +100,7 @@ err_map:
return ERR_PTR(ret);
}
-static struct syscon *node_to_syscon(struct device_node *np)
+static struct syscon *node_to_syscon(struct device_node *np, bool check_clk)
{
struct syscon *entry, *syscon = NULL;
@@ -101,7 +111,7 @@ static struct syscon *node_to_syscon(struct device_node *np)
}
if (!syscon)
- syscon = of_syscon_register(np);
+ syscon = of_syscon_register(np, check_clk);
if (IS_ERR(syscon))
return ERR_CAST(syscon);
@@ -111,27 +121,26 @@ static struct syscon *node_to_syscon(struct device_node *np)
static void __iomem *syscon_node_to_base(struct device_node *np)
{
- struct syscon *syscon = node_to_syscon(np);
+ struct syscon *syscon;
+ struct clk *clk;
+
+ if (!of_device_is_compatible(np, "syscon"))
+ return ERR_PTR(-EINVAL);
+ syscon = node_to_syscon(np, true);
if (IS_ERR(syscon))
return ERR_CAST(syscon);
- return syscon->base;
-}
-
-void __iomem *syscon_base_lookup_by_pdevname(const char *s)
-{
- struct syscon *syscon;
- struct device_d *dev;
-
- for_each_device(dev) {
- if (!strcmp(dev_name(dev), s)) {
- syscon = dev->priv;
- return syscon->base;
- }
- }
+ /* Returning the direct pointer here side steps the regmap
+ * and any specified clock wouldn't be enabled on access.
+ * Deal with this by enabling the clock permanently if any
+ * syscon_node_to_base users exist.
+ */
+ clk = of_clk_get(np, 0);
+ if (!IS_ERR(clk))
+ clk_enable(clk);
- return ERR_PTR(-ENODEV);
+ return syscon->base;
}
void __iomem *syscon_base_lookup_by_phandle(struct device_node *np,
@@ -150,16 +159,31 @@ void __iomem *syscon_base_lookup_by_phandle(struct device_node *np,
return syscon_node_to_base(syscon_np);
}
-struct regmap *syscon_node_to_regmap(struct device_node *np)
+static struct regmap *__device_node_to_regmap(struct device_node *np,
+ bool check_clk)
{
- struct syscon *syscon = node_to_syscon(np);
+ struct syscon *syscon;
+ syscon = node_to_syscon(np, check_clk);
if (IS_ERR(syscon))
return ERR_CAST(syscon);
return syscon->regmap;
}
+struct regmap *device_node_to_regmap(struct device_node *np)
+{
+ return __device_node_to_regmap(np, false);
+}
+
+struct regmap *syscon_node_to_regmap(struct device_node *np)
+{
+ if (!of_device_is_compatible(np, "syscon"))
+ return ERR_PTR(-EINVAL);
+
+ return __device_node_to_regmap(np, true);
+}
+
struct regmap *syscon_regmap_lookup_by_compatible(const char *s)
{
struct device_node *syscon_np;
@@ -193,7 +217,7 @@ struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np,
return regmap;
}
-static int syscon_probe(struct device_d *dev)
+static int syscon_probe(struct device *dev)
{
struct syscon *syscon;
struct resource *res;
@@ -219,17 +243,13 @@ static struct platform_device_id syscon_ids[] = {
{ }
};
-static struct driver_d syscon_driver = {
+static struct driver syscon_driver = {
.name = "syscon",
.probe = syscon_probe,
.id_table = syscon_ids,
};
-static int __init syscon_init(void)
-{
- return platform_driver_register(&syscon_driver);
-}
-core_initcall(syscon_init);
+core_platform_driver(syscon_driver);
MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>");
MODULE_DESCRIPTION("System Control driver");
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-25 08:51:16 +0000