Commit 2a2cd521 authored by Mark Brown's avatar Mark Brown

Merge remote-tracking branches 'regmap/fix/be', 'regmap/fix/doc' and...

Merge remote-tracking branches 'regmap/fix/be', 'regmap/fix/doc' and 'regmap/fix/spmi' into regmap-linus
Device-Tree binding for regmap
The endianness mode of CPU & Device scenarios:
Index Device Endianness properties
1 BE 'big-endian'
2 LE 'little-endian'
3 Native 'native-endian'
For one device driver, which will run in different scenarios above
on different SoCs using the devicetree, we need one way to simplify
Devicetree binding for regmap
Optional properties:
- {big,little,native}-endian: these are boolean properties, if absent
then the implementation will choose a default based on the device
being controlled. These properties are for register values and all
the buffers only. Native endian means that the CPU and device have
the same endianness.
Scenario 1 : CPU in LE mode & device in LE mode.
dev: dev@40031000 {
compatible = "name";
reg = <0x40031000 0x1000>;
native-endian: See common-properties.txt for a definition
Scenario 2 : CPU in LE mode & device in BE mode.
dev: dev@40031000 {
compatible = "name";
reg = <0x40031000 0x1000>;
Regmap defaults to little-endian register access on MMIO based
devices, this is by far the most common setting. On CPU
architectures that typically run big-endian operating systems
(e.g. PowerPC), registers can be defined as big-endian and must
be marked that way in the devicetree.
Scenario 3 : CPU in BE mode & device in BE mode.
dev: dev@40031000 {
compatible = "name";
reg = <0x40031000 0x1000>;
On SoCs that can be operated in both big-endian and little-endian
modes, with a single hardware switch controlling both the endianess
of the CPU and a byteswap for MMIO registers (e.g. many Broadcom MIPS
chips), "native-endian" is used to allow using the same device tree
blob in both cases.
Scenario 4 : CPU in BE mode & device in LE mode.
Scenario 1 : a register set in big-endian mode.
dev: dev@40031000 {
compatible = "name";
compatible = "syscon";
reg = <0x40031000 0x1000>;
......@@ -13,6 +13,7 @@
#include <linux/device.h>
#include <linux/regmap.h>
#include <linux/fs.h>
#include <linux/list.h>
......@@ -23,6 +23,8 @@
#include <linux/regmap.h>
#include <linux/slab.h>
#include "internal.h"
struct regmap_mmio_context {
void __iomem *regs;
unsigned val_bytes;
......@@ -246,7 +248,7 @@ static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev,
ctx->val_bytes = config->val_bits / 8;
ctx->clk = ERR_PTR(-ENODEV);
switch (config->reg_format_endian) {
switch (regmap_get_val_endian(dev, &regmap_mmio, config)) {
......@@ -142,7 +142,7 @@ static int regmap_spmi_ext_read(void *context,
while (val_size) {
len = min_t(size_t, val_size, 8);
err = spmi_ext_register_readl(context, addr, val, val_size);
err = spmi_ext_register_readl(context, addr, val, len);
if (err)
goto err_out;
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