* [PATCH 2/3] i2c: k1: add reset support
2025-12-30 15:06 ` [PATCH 1/3] dt-bindings: i2c: spacemit: add optional resets Encrow Thorne
@ 2025-12-30 15:06 ` Encrow Thorne
2025-12-30 15:06 ` [PATCH 3/3] riscv: dts: spacemit: add reset property Encrow Thorne
2026-01-05 18:44 ` [PATCH 1/3] dt-bindings: i2c: spacemit: add optional resets Rob Herring (Arm)
2 siblings, 0 replies; 9+ messages in thread
From: Encrow Thorne @ 2025-12-30 15:06 UTC (permalink / raw)
To: jyc0019
Cc: alex, andi.shyti, aou, conor+dt, devicetree, dlan, guodong,
krzk+dt, linux-i2c, linux-kernel, linux-riscv, p.zabel, palmer,
pjw, robh, spacemit, troy.mitchell, troymitchell988
The K1 I2C controller provides a reset line that needs to be deasserted
before the controller can be accessed.
Add reset support to the driver to ensure the controller starts in the
required state.
Reviewed-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
Signed-off-by: Encrow Thorne <jyc0019@gmail.com>
---
drivers/i2c/busses/i2c-k1.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/i2c/busses/i2c-k1.c b/drivers/i2c/busses/i2c-k1.c
index d42c03ef5db5..23661c7ddb67 100644
--- a/drivers/i2c/busses/i2c-k1.c
+++ b/drivers/i2c/busses/i2c-k1.c
@@ -10,6 +10,7 @@
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
+ #include <linux/reset.h>
/* spacemit i2c registers */
#define SPACEMIT_ICR 0x0 /* Control register */
@@ -534,6 +535,7 @@ static int spacemit_i2c_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct device_node *of_node = pdev->dev.of_node;
struct spacemit_i2c_dev *i2c;
+ struct reset_control *rst;
int ret;
i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
@@ -578,6 +580,11 @@ static int spacemit_i2c_probe(struct platform_device *pdev)
if (IS_ERR(clk))
return dev_err_probe(dev, PTR_ERR(clk), "failed to enable bus clock");
+ rst = devm_reset_control_get_optional_exclusive_deasserted(dev, NULL);
+ if (IS_ERR(rst))
+ return dev_err_probe(dev, PTR_ERR(rst),
+ "failed to acquire deasserted reset\n");
+
spacemit_i2c_reset(i2c);
i2c_set_adapdata(&i2c->adapt, i2c);
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH 3/3] riscv: dts: spacemit: add reset property
2025-12-30 15:06 ` [PATCH 1/3] dt-bindings: i2c: spacemit: add optional resets Encrow Thorne
2025-12-30 15:06 ` [PATCH 2/3] i2c: k1: add reset support Encrow Thorne
@ 2025-12-30 15:06 ` Encrow Thorne
2026-01-07 14:22 ` Andi Shyti
2026-01-05 18:44 ` [PATCH 1/3] dt-bindings: i2c: spacemit: add optional resets Rob Herring (Arm)
2 siblings, 1 reply; 9+ messages in thread
From: Encrow Thorne @ 2025-12-30 15:06 UTC (permalink / raw)
To: jyc0019
Cc: alex, andi.shyti, aou, conor+dt, devicetree, dlan, guodong,
krzk+dt, linux-i2c, linux-kernel, linux-riscv, p.zabel, palmer,
pjw, robh, spacemit, troy.mitchell, troymitchell988
Add resets property to K1 I2C node.
---
arch/riscv/boot/dts/spacemit/k1.dtsi | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/riscv/boot/dts/spacemit/k1.dtsi b/arch/riscv/boot/dts/spacemit/k1.dtsi
index 7818ca4979b6..085987643638 100644
--- a/arch/riscv/boot/dts/spacemit/k1.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k1.dtsi
@@ -367,6 +367,7 @@ i2c0: i2c@d4010800 {
<&syscon_apbc CLK_TWSI0_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI0>;
interrupts = <36>;
status = "disabled";
};
@@ -380,6 +381,7 @@ i2c1: i2c@d4011000 {
<&syscon_apbc CLK_TWSI1_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI1>;
interrupts = <37>;
status = "disabled";
};
@@ -393,6 +395,7 @@ i2c2: i2c@d4012000 {
<&syscon_apbc CLK_TWSI2_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI2>;
interrupts = <38>;
status = "disabled";
};
@@ -406,6 +409,7 @@ i2c4: i2c@d4012800 {
<&syscon_apbc CLK_TWSI4_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI4>;
interrupts = <40>;
status = "disabled";
};
@@ -419,6 +423,7 @@ i2c5: i2c@d4013800 {
<&syscon_apbc CLK_TWSI5_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI5>;
interrupts = <41>;
status = "disabled";
};
@@ -443,6 +448,7 @@ i2c6: i2c@d4018800 {
<&syscon_apbc CLK_TWSI6_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI6>;
interrupts = <70>;
status = "disabled";
};
@@ -546,6 +552,7 @@ i2c7: i2c@d401d000 {
<&syscon_apbc CLK_TWSI7_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI7>;
interrupts = <18>;
status = "disabled";
};
@@ -559,6 +566,7 @@ i2c8: i2c@d401d800 {
<&syscon_apbc CLK_TWSI8_BUS>;
clock-names = "func", "bus";
clock-frequency = <400000>;
+ resets = <&syscon_apbc RESET_TWSI8>;
interrupts = <19>;
status = "disabled";
};
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH 3/3] riscv: dts: spacemit: add reset property
2025-12-30 15:06 ` [PATCH 3/3] riscv: dts: spacemit: add reset property Encrow Thorne
@ 2026-01-07 14:22 ` Andi Shyti
2026-01-07 16:23 ` Encrow Thorne
0 siblings, 1 reply; 9+ messages in thread
From: Andi Shyti @ 2026-01-07 14:22 UTC (permalink / raw)
To: Encrow Thorne
Cc: alex, aou, conor+dt, devicetree, dlan, guodong, krzk+dt,
linux-i2c, linux-kernel, linux-riscv, p.zabel, palmer, pjw, robh,
spacemit, troy.mitchell, troymitchell988
Hi Encrow,
On Tue, Dec 30, 2025 at 11:06:53PM +0800, Encrow Thorne wrote:
> Add resets property to K1 I2C node.
> ---
> arch/riscv/boot/dts/spacemit/k1.dtsi | 8 ++++++++
> 1 file changed, 8 insertions(+)
how is this patch formatted?
Andi
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 3/3] riscv: dts: spacemit: add reset property
2026-01-07 14:22 ` Andi Shyti
@ 2026-01-07 16:23 ` Encrow Thorne
2026-01-07 17:51 ` Andi Shyti
0 siblings, 1 reply; 9+ messages in thread
From: Encrow Thorne @ 2026-01-07 16:23 UTC (permalink / raw)
To: Andi Shyti
Cc: alex, aou, conor+dt, devicetree, dlan, guodong, krzk+dt,
linux-i2c, linux-kernel, linux-riscv, p.zabel, palmer, pjw, robh,
spacemit, troy.mitchell, troymitchell988
On Wed, Jan 07, 2026 at 03:22:42PM +0100, Andi Shyti wrote:
Hi Andi,
> Hi Encrow,
>
> On Tue, Dec 30, 2025 at 11:06:53PM +0800, Encrow Thorne wrote:
> > Add resets property to K1 I2C node.
> > ---
> > arch/riscv/boot/dts/spacemit/k1.dtsi | 8 ++++++++
> > 1 file changed, 8 insertions(+)
>
> how is this patch formatted?
>
Sorry, I forgot to add the version number when I resent it.
The initial sending process was interrupted, so I
manually regenerated the patches using git format-patch
and sent them again.I have verified locally that the
entire patch series applies cleanly.
Please let me know if you find any other formatting issues.
Encrow
> Andi
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 3/3] riscv: dts: spacemit: add reset property
2026-01-07 16:23 ` Encrow Thorne
@ 2026-01-07 17:51 ` Andi Shyti
0 siblings, 0 replies; 9+ messages in thread
From: Andi Shyti @ 2026-01-07 17:51 UTC (permalink / raw)
To: Encrow Thorne
Cc: alex, aou, conor+dt, devicetree, dlan, guodong, krzk+dt,
linux-i2c, linux-kernel, linux-riscv, p.zabel, palmer, pjw, robh,
spacemit, troy.mitchell, troymitchell988
Hi Encrow,
On Thu, Jan 08, 2026 at 12:23:43AM +0800, Encrow Thorne wrote:
> On Wed, Jan 07, 2026 at 03:22:42PM +0100, Andi Shyti wrote:
> Hi Andi,
> > Hi Encrow,
> >
> > On Tue, Dec 30, 2025 at 11:06:53PM +0800, Encrow Thorne wrote:
> > > Add resets property to K1 I2C node.
> > > ---
> > > arch/riscv/boot/dts/spacemit/k1.dtsi | 8 ++++++++
> > > 1 file changed, 8 insertions(+)
> >
> > how is this patch formatted?
> >
> Sorry, I forgot to add the version number when I resent it.
you also forgot the tag section :-)
No worries, I took patch 1 and 2 into i2c/i2c-host branch.
Thanks,
Andi
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 1/3] dt-bindings: i2c: spacemit: add optional resets
2025-12-30 15:06 ` [PATCH 1/3] dt-bindings: i2c: spacemit: add optional resets Encrow Thorne
2025-12-30 15:06 ` [PATCH 2/3] i2c: k1: add reset support Encrow Thorne
2025-12-30 15:06 ` [PATCH 3/3] riscv: dts: spacemit: add reset property Encrow Thorne
@ 2026-01-05 18:44 ` Rob Herring (Arm)
2 siblings, 0 replies; 9+ messages in thread
From: Rob Herring (Arm) @ 2026-01-05 18:44 UTC (permalink / raw)
To: Encrow Thorne
Cc: guodong, devicetree, krzk+dt, aou, palmer, spacemit, linux-riscv,
conor+dt, pjw, troy.mitchell, p.zabel, linux-i2c, troymitchell988,
dlan, linux-kernel, andi.shyti, alex
On Tue, 30 Dec 2025 23:06:51 +0800, Encrow Thorne wrote:
> The I2C controller requires a reset to ensure it starts from a clean state.
>
> Add the 'resets' property to support this hardware requirement.
>
> Reviewed-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
> Signed-off-by: Encrow Thorne <jyc0019@gmail.com>
> ---
> Documentation/devicetree/bindings/i2c/spacemit,k1-i2c.yaml | 3 +++
> 1 file changed, 3 insertions(+)
>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
^ permalink raw reply [flat|nested] 9+ messages in thread