Re: [PATCH v2 2/2] Input: pm8xxx-vib - Add support for more PMICs

From: Fenglin Wu
Date: Wed Jul 19 2023 - 00:09:38 EST




On 7/18/2023 7:04 PM, Dmitry Baryshkov wrote:
On Tue, 18 Jul 2023 at 13:55, Fenglin Wu <quic_fenglinw@xxxxxxxxxxx> wrote:



On 7/18/2023 5:41 PM, Dmitry Baryshkov wrote:
On Tue, 18 Jul 2023 at 09:58, Fenglin Wu <quic_fenglinw@xxxxxxxxxxx> wrote:



On 7/18/2023 2:44 PM, Dmitry Baryshkov wrote:
On Tue, 18 Jul 2023 at 09:27, Fenglin Wu <quic_fenglinw@xxxxxxxxxxx> wrote:

Add support for vibrator module inside PMI632, PM7250B, PM7325B.
It is very similar to vibrator inside PM8xxx but just the drive
amplitude is controlled through 2 bytes registers.

Signed-off-by: Fenglin Wu <quic_fenglinw@xxxxxxxxxxx>
---
drivers/input/misc/pm8xxx-vibrator.c | 48 ++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)

diff --git a/drivers/input/misc/pm8xxx-vibrator.c b/drivers/input/misc/pm8xxx-vibrator.c
index 04cb87efd799..213fdfd47c7f 100644
--- a/drivers/input/misc/pm8xxx-vibrator.c
+++ b/drivers/input/misc/pm8xxx-vibrator.c
@@ -25,6 +25,9 @@ struct pm8xxx_regs {
unsigned int drv_addr;
unsigned int drv_mask;
unsigned int drv_shift;
+ unsigned int drv_addr2;
+ unsigned int drv_mask2;
+ unsigned int drv_shift2;
unsigned int drv_en_manual_mask;
};

@@ -44,6 +47,42 @@ static struct pm8xxx_regs pm8916_regs = {
.drv_en_manual_mask = 0,
};

+static struct pm8xxx_regs pmi632_regs = {
+ .enable_addr = 0x5746,
+ .enable_mask = BIT(7),
+ .drv_addr = 0x5740,
+ .drv_mask = 0xff,
+ .drv_shift = 0,
+ .drv_addr2 = 0x5741,
+ .drv_mask2 = 0x0f,
+ .drv_shift2 = 8,

I see that you are just expanding what was done for SSBI PMICs and
later expanded to support pm8916. However it might be better to drop
the hardcoded .drv_addr (and drv_addr2) and read address from DT
instead.


Right, this is the simplest change without updating the code logic too
much. If we decided to read .drv_addr and .drv_add2 from DT, we will
have to read .enable_addr along with all other mask/shift for each
register address from DT as well because they are not consistent from
target to target. I don't know how would you suggest to add the DT
properties for all of them, but if we end up to add a property for each
of them, it won't be cleaner than hard-coding them.

No, we (correctly) have device compatibles for that. The issue with
hardcoding register addresses is that it adds extra issues here.

If I understand correctly, we have several 'generation':
- SSBI PMIC, shifted 5-bit mask, en_manual_mask, no enable_register.
- older SPMI PMIC, 5 bit drv_mask, 0 en_manual_mask, enable register at +6
- new SPMI PMIC, 12 bit drv_mask, 0 en_manual_mask, enable register at +6

For the last generation you are adding three independent entries,
while the block looks the same. If you remove drv_addr (and get it
from reg property), it would allow us to keep only the functional data
in struct pm8xxxx_regs (masks / shifts).


Okay, let me know if I understood it correctly, this is what you are
suggesting:

- hard code the mask/shifts and still keep them in struct pm8xxx_regs,
combine the drv_mask2 to the upper byte of the drv_mask, so we will
have following data structure for the 3rd generation vibrator

static struct pm8xxx_regs pm7250b_regs = {
.enable_addr = 0x5346,
.enable_mask = BIT(7),
.drv_mask = 0xfff,
.drv_shift = 0,
.drv_en_manual_mask = 0,
};


- move the drv_addr/drv_addr2 into DT, read them from 'reg' property.
Because of 'mfd/qcom,spmi-pmic.yaml' has defined the 'address-cells'
as 1 and the 'size-cells' as 0 for qcom spmi devices, we couldn't
specify the address size to 2 even the drv_addr for the 3rd
generation vibrator is 2 adjacent bytes. So we will end of having
following DT scheme:

For the 2nd generation which only has drv_addr
vibrator@c041 {
compatible = "qcom,pm8916-vib";
reg = <0xc041>; /* drv_addr */

No. This is <0xc000>.

...
};

For the 3rd generation which has both drv_addr and drv_addr2
vibrator@5340 {
compatible = "qcom,pm7250b-vib";
reg = <0x5340>, /* drv_addr */
<0x5341>; /* drv_addr2 */
...
};

Not sure how do you feel, I actually don't see too much benefit than
hard-coding them in the driver.
We will end up having code to check how many u32 value in the 'reg' and
only assign it to drv_addr2 when the 2nd is available, also when
programming drv_addr2 register, the driver will always assume the mask
is in the upper byte of the drv_mask and the shift to the drive level is
8 (this seems hacky to me and it was my biggest concern while I made
this change, and it led me to defining drv_shift2/drv_mask2 along with
drv_addr2).

We only need drv_addr2 if drv_mask has more than 8 bits. So you don't
have to specify it in the DT. It is always equal to base_reg + 0x41.
The same way drv_addr is always equal to base_reg + 0x40 for all
SPMI-based PMIC vibrator devices.


Thanks. I got it now, I agree this will be beneficial for the case that different PMICs have the same vibrator module but with different register base address. I am going to change it to this way, let me know if this is what you thought:

@@ -25,6 +29,9 @@ struct pm8xxx_regs {
unsigned int drv_addr;
unsigned int drv_mask;
unsigned int drv_shift;
+ unsigned int drv_addr2;
+ unsigned int drv_mask2;
+ unsigned int drv_shift2;
unsigned int drv_en_manual_mask;
};

+static struct pm8xxx_regs spmi_vib_regs = {
+ .enable_mask = BIT(7),
+ .drv_mask = 0xff,
+ .drv_shift = 0,
+ .drv_mask2 = 0xf,
+ .drv_shift2 = 8,
+ .drv_en_manual_mask = 0,
+};
+

+#define SPMI_VIB_VSET_LB_REG 0x40
+#define SPMI_VIB_VSET_UP_REG 0x41
+#define SPMI_VIB_EN_CTL_REG 0x46
+

regs = of_device_get_match_data(&pdev->dev);

+ if (regs->drv_addr == 0) {
+ rc = fwnode_property_read_u32(pdev->dev.fwnode,
+ "reg", &reg_base);
+ if (rc < 0)
+ return rc;
+
+ regs->enable_addr = reg_base + SPMI_VIB_EN_CTL_REG;
+ regs->drv_addr = reg_base + SPMI_VIB_VSET_LB_REG;
+ regs->drv_addr2 = reg_base + SPMI_VIB_VSET_UP_REG;
+ }
+


@@ -242,6 +277,7 @@ static const struct of_device_id pm8xxx_vib_id_table[] = {
{ .compatible = "qcom,pm8058-vib", .data = &pm8058_regs },
{ .compatible = "qcom,pm8921-vib", .data = &pm8058_regs },
{ .compatible = "qcom,pm8916-vib", .data = &pm8916_regs },
+ ( .compabitle = "qcom,spmi-vib", .data = &spmi_vib_regs },
{ }







+ .drv_en_manual_mask = 0,
+};
+
+static struct pm8xxx_regs pm7250b_regs = {
+ .enable_addr = 0x5346,
+ .enable_mask = BIT(7),
+ .drv_addr = 0x5340,
+ .drv_mask = 0xff,
+ .drv_shift = 0,
+ .drv_addr2 = 0x5341,
+ .drv_mask2 = 0x0f,
+ .drv_shift2 = 8,
+ .drv_en_manual_mask = 0,
+};
+
+static struct pm8xxx_regs pm7325b_regs = {
+ .enable_addr = 0xdf46,
+ .enable_mask = BIT(7),
+ .drv_addr = 0xdf40,
+ .drv_mask = 0xff,
+ .drv_shift = 0,
+ .drv_addr2 = 0xdf41,
+ .drv_mask2 = 0x0f,
+ .drv_shift2 = 8,
+ .drv_en_manual_mask = 0,
+};
+
/**
* struct pm8xxx_vib - structure to hold vibrator data
* @vib_input_dev: input device supporting force feedback
@@ -87,6 +126,12 @@ static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
return rc;

vib->reg_vib_drv = val;
+ if (regs->drv_addr2 != 0 && on) {
+ val = (vib->level << regs->drv_shift2) & regs->drv_mask2;
+ rc = regmap_write(vib->regmap, regs->drv_addr2, val);
+ if (rc < 0)
+ return rc;
+ }

if (regs->enable_mask)
rc = regmap_update_bits(vib->regmap, regs->enable_addr,
@@ -242,6 +287,9 @@ static const struct of_device_id pm8xxx_vib_id_table[] = {
{ .compatible = "qcom,pm8058-vib", .data = &pm8058_regs },
{ .compatible = "qcom,pm8921-vib", .data = &pm8058_regs },
{ .compatible = "qcom,pm8916-vib", .data = &pm8916_regs },
+ { .compatible = "qcom,pmi632-vib", .data = &pmi632_regs },
+ { .compatible = "qcom,pm7250b-vib", .data = &pm7250b_regs },
+ { .compatible = "qcom,pm7325b-vib", .data = &pm7325b_regs },
{ }
};
MODULE_DEVICE_TABLE(of, pm8xxx_vib_id_table);
--
2.25.1