diff options
| author | Baolin Wang <baolin.wang@linaro.org> | 2017-12-25 14:37:10 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2018-01-12 18:32:55 +0000 |
| commit | 3bafc09e779710abaa7b836fe3bbeeeab7754c2b (patch) | |
| tree | 1c78fbe67c3ca13bf771978047d3582079766415 | |
| parent | a4887813c3a9481ab87c8a71ab1de50b975cc823 (diff) | |
| download | linux-3bafc09e779710abaa7b836fe3bbeeeab7754c2b.tar.bz2 | |
mfd: syscon: Add hardware spinlock support
Some system control registers need hardware spinlock to synchronize
between the multiple subsystems, so we should add hardware spinlock
support for syscon.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | Documentation/devicetree/bindings/mfd/syscon.txt | 8 | ||||
| -rw-r--r-- | drivers/mfd/syscon.c | 19 |
2 files changed, 27 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt index 8b92d4576c42..25d9e9c2fd53 100644 --- a/Documentation/devicetree/bindings/mfd/syscon.txt +++ b/Documentation/devicetree/bindings/mfd/syscon.txt @@ -16,9 +16,17 @@ Required properties: Optional property: - reg-io-width: the size (in bytes) of the IO accesses that should be performed on the device. +- hwlocks: reference to a phandle of a hardware spinlock provider node. Examples: gpr: iomuxc-gpr@20e0000 { compatible = "fsl,imx6q-iomuxc-gpr", "syscon"; reg = <0x020e0000 0x38>; + hwlocks = <&hwlock1 1>; +}; + +hwlock1: hwspinlock@40500000 { + ... + reg = <0x40500000 0x1000>; + #hwlock-cells = <1>; }; diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index b93fe4c4957a..7eaa40bc703f 100644 --- a/drivers/mfd/syscon.c +++ b/drivers/mfd/syscon.c @@ -13,6 +13,7 @@ */ #include <linux/err.h> +#include <linux/hwspinlock.h> #include <linux/io.h> #include <linux/module.h> #include <linux/list.h> @@ -87,6 +88,24 @@ static struct syscon *of_syscon_register(struct device_node *np) if (ret) reg_io_width = 4; + ret = of_hwspin_lock_get_id(np, 0); + if (ret > 0 || (IS_ENABLED(CONFIG_HWSPINLOCK) && ret == 0)) { + syscon_config.use_hwlock = true; + syscon_config.hwlock_id = ret; + syscon_config.hwlock_mode = HWLOCK_IRQSTATE; + } else if (ret < 0) { + switch (ret) { + case -ENOENT: + /* Ignore missing hwlock, it's optional. */ + break; + default: + pr_err("Failed to retrieve valid hwlock: %d\n", ret); + /* fall-through */ + case -EPROBE_DEFER: + goto err_regmap; + } + } + 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; |