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Message-ID: <CAA8EJpoeFwu7P7jEqhmwttAeF4VAhaCSaKP4XrUQz1YVsg9zvw@mail.gmail.com>
Date: Wed, 19 Jul 2023 11:02:42 +0300
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Fenglin Wu <quic_fenglinw@...cinc.com>
Cc: linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org,
Andy Gross <agross@...nel.org>,
Bjorn Andersson <andersson@...nel.org>,
Konrad Dybcio <konrad.dybcio@...aro.org>,
Dmitry Torokhov <dmitry.torokhov@...il.com>,
linux-input@...r.kernel.org, quic_collinsd@...cinc.com,
quic_subbaram@...cinc.com, quic_kamalw@...cinc.com,
jestar@....qualcomm.com, quic_huliu@...cinc.com
Subject: Re: [PATCH v2 2/2] Input: pm8xxx-vib - Add support for more PMICs
On Wed, 19 Jul 2023 at 07:09, Fenglin Wu <quic_fenglinw@...cinc.com> wrote:
>
>
>
> On 7/18/2023 7:04 PM, Dmitry Baryshkov wrote:
> > On Tue, 18 Jul 2023 at 13:55, Fenglin Wu <quic_fenglinw@...cinc.com> wrote:
> >>
> >>
> >>
> >> On 7/18/2023 5:41 PM, Dmitry Baryshkov wrote:
> >>> On Tue, 18 Jul 2023 at 09:58, Fenglin Wu <quic_fenglinw@...cinc.com> wrote:
> >>>>
> >>>>
> >>>>
> >>>> On 7/18/2023 2:44 PM, Dmitry Baryshkov wrote:
> >>>>> On Tue, 18 Jul 2023 at 09:27, Fenglin Wu <quic_fenglinw@...cinc.com> 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@...cinc.com>
> >>>>>> ---
> >>>>>> 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;
Unused
> >>>>>> + 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@...1 {
> >> 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@...0 {
> >> 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,
> +};
Ideally the static data should be const. I'd suggest moving
drv_addr/drv_addr2 to struct pm8xxx_vib.
> +
>
> +#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", ®_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;
Yes, this looks good (except s/regs->/vib->/). Moreover this also
applies to pm8916. I'd suggest splitting this into two patches: first,
refactor pm8916 support to use reg, then add support for new devices.
> + }
> +
>
>
> @@ -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
> >>>>>>
> >>>>>
> >>>>>
> >>>
> >>>
> >>>
> >
> >
> >
--
With best wishes
Dmitry
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