2019-02-28 13:36:44

by Pankaj Bansal

[permalink] [raw]
Subject: [PATCH v5 2/2] drivers: mux: Add Generic regmap bitfield-based multiplexer in mmio-mux

Generic register bitfield-based multiplexer that controls the multiplexer
producer defined under a parent node.
The driver corresponding to parent node provides register read/write
capabilities.

Signed-off-by: Pankaj Bansal <[email protected]>
---

Notes:
V5:
- No Change
V4:
- As per Peter's suggestion fixup the NULL from dev_get_regmap as early as
possible using ternary operator.
V3:
- Added the patch in series with device tree binding patch
- Added the NULL return handling for regmap
V2:
- removed seperate driver regmap.c and added the regmap function in mmio.c
based on compatible field, the syscon or regmap function would be called
- Modified the KConfig as per Peter's comments

drivers/mux/Kconfig | 12 ++++++------
drivers/mux/mmio.c | 6 +++++-
2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index 7659d6c5f718..e5c571fd232c 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -46,14 +46,14 @@ config MUX_GPIO
be called mux-gpio.

config MUX_MMIO
- tristate "MMIO register bitfield-controlled Multiplexer"
- depends on (OF && MFD_SYSCON) || COMPILE_TEST
+ tristate "MMIO/Regmap register bitfield-controlled Multiplexer"
+ depends on OF || COMPILE_TEST
help
- MMIO register bitfield-controlled Multiplexer controller.
+ MMIO/Regmap register bitfield-controlled Multiplexer controller.

- The driver builds multiplexer controllers for bitfields in a syscon
- register. For N bit wide bitfields, there will be 2^N possible
- multiplexer states.
+ The driver builds multiplexer controllers for bitfields in either
+ a syscon register or a driver regmap register. For N bit wide
+ bitfields, there will be 2^N possible multiplexer states.

To compile the driver as a module, choose M here: the module will
be called mux-mmio.
diff --git a/drivers/mux/mmio.c b/drivers/mux/mmio.c
index 935ac44aa209..44a7a0e885b8 100644
--- a/drivers/mux/mmio.c
+++ b/drivers/mux/mmio.c
@@ -28,6 +28,7 @@ static const struct mux_control_ops mux_mmio_ops = {

static const struct of_device_id mux_mmio_dt_ids[] = {
{ .compatible = "mmio-mux", },
+ { .compatible = "reg-mux", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mux_mmio_dt_ids);
@@ -43,7 +44,10 @@ static int mux_mmio_probe(struct platform_device *pdev)
int ret;
int i;

- regmap = syscon_node_to_regmap(np->parent);
+ if (of_device_is_compatible(np, "mmio-mux"))
+ regmap = syscon_node_to_regmap(np->parent);
+ else
+ regmap = dev_get_regmap(dev->parent, NULL) ?: ERR_PTR(-ENODEV);
if (IS_ERR(regmap)) {
ret = PTR_ERR(regmap);
dev_err(dev, "failed to get regmap: %d\n", ret);
--
2.17.1