[PATCH 2/2] i2c: omap: Add support for setting mux

Jayesh Choudhary
2025-03-18T10:36:40Z

Some SoCs require muxes in the routing for SDA and SCL lines.
Therefore, add support for setting the mux by reading the mux-states
property from the dt-node.

Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
---
drivers/i2c/busses/Kconfig | 1 +
drivers/i2c/busses/i2c-omap.c | 22 ++++++++++++++++++++++
2 files changed, 23 insertions(+)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index fc438f445771..0648e58b083e 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -940,6 +940,7 @@ config I2C_OMAP
tristate "OMAP I2C adapter"
depends on ARCH_OMAP || ARCH_K3 || COMPILE_TEST
default MACH_OMAP_OSK
+ select MULTIPLEXER
help
If you say yes to this option, support will be included for the
I2C interface on the Texas Instruments OMAP1/2 family of processors.
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index f18c3e74b076..16afb9ca19bb 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -24,6 +24,7 @@
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/mux/consumer.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/platform_data/i2c-omap.h>
@@ -211,6 +212,7 @@ struct omap_i2c_dev {
u16 syscstate;
u16 westate;
u16 errata;
+ struct mux_state *mux_state;
};

static const u8 reg_map_ip_v1[] = {
@@ -1452,6 +1454,23 @@ omap_i2c_probe(struct platform_device *pdev)
(1000 * omap->speed / 8);
}

+ if (of_property_read_bool(node, "mux-states")) {
+ struct mux_state *mux_state;
+
+ mux_state = devm_mux_state_get(&pdev->dev, NULL);
+ if (IS_ERR(mux_state)) {
+ r = PTR_ERR(mux_state);
+ dev_dbg(&pdev->dev, "failed to get I2C mux: %d\n", r);
+ goto err_disable_pm;
+ }
+ omap->mux_state = mux_state;
+ r = mux_state_select(omap->mux_state);
+ if (r) {
+ dev_err(&pdev->dev, "failed to select I2C mux: %d\n", r);
+ goto err_disable_pm;
+ }
+ }
+
/* reset ASAP, clearing any IRQs */
omap_i2c_init(omap);

@@ -1511,6 +1530,9 @@ static void omap_i2c_remove(struct platform_device *pdev)

i2c_del_adapter(&omap->adapter);

+ if (omap->mux_state)
+ mux_state_deselect(omap->mux_state);
+
ret = pm_runtime_get_sync(&pdev->dev);
if (ret < 0)
dev_err(omap->dev, "Failed to resume hardware, skip disable\n");
--
2.34.1