Re: [PATCH] pinctrl: qcom: Add egpio feature support
From: Rajendra Nayak
Date: Tue Sep 21 2021 - 06:39:39 EST
On 9/20/2021 6:14 AM, Bjorn Andersson wrote:
On Fri 17 Sep 01:37 CDT 2021, Rajendra Nayak wrote:
From: Prasad Sodagudi <psodagud@xxxxxxxxxxxxxx>
egpio is a scheme which allows special power Island Domain IOs
(LPASS,SSC) to be reused as regular chip GPIOs by muxing regular
TLMM functions with Island Domain functions.
With this scheme, an IO can be controlled both by the cpu running
linux and the Island processor. This provides great flexibility to
re-purpose the Island IOs for regular TLMM usecases.
2 new bits are added to ctl_reg, egpio_present is a read only bit
which shows if egpio feature is available or not on a given gpio.
egpio_enable is the read/write bit and only effective if egpio_present
is 1. Once its set, the Island IO is controlled from Chip TLMM.
egpio_enable when set to 0 means the GPIO is used as Island Domain IO.
The support exists on most recent qcom SoCs, and we add support
for sm8150/sm8250/sm8350 and sc7280 as part of this patch.
I was under the impression that this feature would allow you to
repurpose pins for use either by the remote island or by apps.
thats right, you can repurpose the pins for usage by apps by setting
the egpio_enable to 1, when set to 0 its owned by the island processor.
But if I understand your proposal, you check to see if the pin is
"egpio capable" for a pin and if so just sets the bit - muxing it to
apps (or the island?).
Right, so if there is a request for a egpio-capable pin, the driver
flips the ownership. Are you suggesting having some kind of checks to determine
who should own it?
It seems reasonable that this would be another pinmux state for these
pins, rather than just flipping them all in one or the other direction.
hmm, I don't understand. This is not a pinmux state, its a switch to decide
the ownership.
These egpio pins have regulator mux functions, some for apps, some for the
island processor, they might not always be used as gpios.
PS. When I spoke with Prasad about this a couple of years ago, I think
we talked about representing this as a pinconf property, but it seems to
make more sense to me now that it would be a pinmux state.
Regards,
Bjorn
Signed-off-by: Prasad Sodagudi <psodagud@xxxxxxxxxxxxxx>
[rnayak: rewrite commit log, minor rebase]
Signed-off-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
---
drivers/pinctrl/qcom/pinctrl-msm.c | 4 ++++
drivers/pinctrl/qcom/pinctrl-msm.h | 2 ++
drivers/pinctrl/qcom/pinctrl-sc7280.c | 2 ++
drivers/pinctrl/qcom/pinctrl-sm8150.c | 2 ++
drivers/pinctrl/qcom/pinctrl-sm8250.c | 2 ++
drivers/pinctrl/qcom/pinctrl-sm8350.c | 2 ++
6 files changed, 14 insertions(+)
diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index 8476a8a..f4a2343 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -220,6 +220,10 @@ static int msm_pinmux_set_mux(struct pinctrl_dev *pctldev,
val = msm_readl_ctl(pctrl, g);
val &= ~mask;
val |= i << g->mux_bit;
+ /* Check if egpio present and enable that feature */
+ if (val & BIT(g->egpio_present))
+ val |= BIT(g->egpio_enable);
+
msm_writel_ctl(val, pctrl, g);
raw_spin_unlock_irqrestore(&pctrl->lock, flags);
diff --git a/drivers/pinctrl/qcom/pinctrl-msm.h b/drivers/pinctrl/qcom/pinctrl-msm.h
index e31a516..3635b31 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.h
+++ b/drivers/pinctrl/qcom/pinctrl-msm.h
@@ -77,6 +77,8 @@ struct msm_pingroup {
unsigned drv_bit:5;
unsigned od_bit:5;
+ unsigned egpio_enable:5;
+ unsigned egpio_present:5;
unsigned oe_bit:5;
unsigned in_bit:5;
unsigned out_bit:5;
diff --git a/drivers/pinctrl/qcom/pinctrl-sc7280.c b/drivers/pinctrl/qcom/pinctrl-sc7280.c
index afddf6d..607d459 100644
--- a/drivers/pinctrl/qcom/pinctrl-sc7280.c
+++ b/drivers/pinctrl/qcom/pinctrl-sc7280.c
@@ -43,6 +43,8 @@
.mux_bit = 2, \
.pull_bit = 0, \
.drv_bit = 6, \
+ .egpio_enable = 12, \
+ .egpio_present = 11, \
.oe_bit = 9, \
.in_bit = 0, \
.out_bit = 1, \
diff --git a/drivers/pinctrl/qcom/pinctrl-sm8150.c b/drivers/pinctrl/qcom/pinctrl-sm8150.c
index 7359bae..63a625a 100644
--- a/drivers/pinctrl/qcom/pinctrl-sm8150.c
+++ b/drivers/pinctrl/qcom/pinctrl-sm8150.c
@@ -56,6 +56,8 @@ enum {
.mux_bit = 2, \
.pull_bit = 0, \
.drv_bit = 6, \
+ .egpio_enable = 12, \
+ .egpio_present = 11, \
.oe_bit = 9, \
.in_bit = 0, \
.out_bit = 1, \
diff --git a/drivers/pinctrl/qcom/pinctrl-sm8250.c b/drivers/pinctrl/qcom/pinctrl-sm8250.c
index af144e7..ad4fd94 100644
--- a/drivers/pinctrl/qcom/pinctrl-sm8250.c
+++ b/drivers/pinctrl/qcom/pinctrl-sm8250.c
@@ -57,6 +57,8 @@ enum {
.mux_bit = 2, \
.pull_bit = 0, \
.drv_bit = 6, \
+ .egpio_enable = 12, \
+ .egpio_present = 11, \
.oe_bit = 9, \
.in_bit = 0, \
.out_bit = 1, \
diff --git a/drivers/pinctrl/qcom/pinctrl-sm8350.c b/drivers/pinctrl/qcom/pinctrl-sm8350.c
index 4d8f863..bb436dc 100644
--- a/drivers/pinctrl/qcom/pinctrl-sm8350.c
+++ b/drivers/pinctrl/qcom/pinctrl-sm8350.c
@@ -46,6 +46,8 @@
.mux_bit = 2, \
.pull_bit = 0, \
.drv_bit = 6, \
+ .egpio_enable = 12, \
+ .egpio_present = 11, \
.oe_bit = 9, \
.in_bit = 0, \
.out_bit = 1, \
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation