Re: [PATCH 1/7] mfd: qcom-spmi-pmic: expose the PMIC revid information to clients

Jonathan Cameron
2021-12-12T17:22:21Z

On Sat, 11 Dec 2021 02:22:18 +0000
Caleb Connolly <caleb.connolly@linaro.org> wrote:

> From: Caleb Connolly <caleb.connolly@linaro.org>
>
> Some PMIC functions such as the RRADC need to be aware of the PMIC
> chip revision information to implement errata or otherwise adjust
> behaviour, export the PMIC information to enable this.
>
> This is specifically required to enable the RRADC to adjust
> coefficients based on which chip fab the PMIC was produced in,
> this can vary per unique device and therefore has to be read at
> runtime.
>
> Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

Hi Calib,

Comments inline.

Jonathan

> ---
> drivers/mfd/qcom-spmi-pmic.c | 103 +++++++++++++++++------------------
> include/soc/qcom/qcom-pmic.h | 58 ++++++++++++++++++++
> 2 files changed, 108 insertions(+), 53 deletions(-)
> create mode 100644 include/soc/qcom/qcom-pmic.h
>
> diff --git a/drivers/mfd/qcom-spmi-pmic.c b/drivers/mfd/qcom-spmi-pmic.c
> index 1cacc00aa6c9..78530c1aca4b 100644
> --- a/drivers/mfd/qcom-spmi-pmic.c
> +++ b/drivers/mfd/qcom-spmi-pmic.c
> @@ -3,51 +3,25 @@
> * Copyright (c) 2014, The Linux Foundation. All rights reserved.
> */
>
> +#include <linux/device.h>
> +#include <linux/gfp.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> +#include <linux/slab.h>
> #include <linux/spmi.h>
> +#include <linux/string.h>
> #include <linux/regmap.h>
> #include <linux/of_platform.h>
> +#include <soc/qcom/qcom-pmic.h>
>
> #define PMIC_REV2 0x101
> #define PMIC_REV3 0x102
> #define PMIC_REV4 0x103
> #define PMIC_TYPE 0x104
> #define PMIC_SUBTYPE 0x105
> -
> +#define PMIC_FAB_ID 0x1f2
> #define PMIC_TYPE_VALUE 0x51
>
> -#define COMMON_SUBTYPE 0x00
> -#define PM8941_SUBTYPE 0x01
> -#define PM8841_SUBTYPE 0x02
> -#define PM8019_SUBTYPE 0x03
> -#define PM8226_SUBTYPE 0x04
> -#define PM8110_SUBTYPE 0x05
> -#define PMA8084_SUBTYPE 0x06
> -#define PMI8962_SUBTYPE 0x07
> -#define PMD9635_SUBTYPE 0x08
> -#define PM8994_SUBTYPE 0x09
> -#define PMI8994_SUBTYPE 0x0a
> -#define PM8916_SUBTYPE 0x0b
> -#define PM8004_SUBTYPE 0x0c
> -#define PM8909_SUBTYPE 0x0d
> -#define PM8028_SUBTYPE 0x0e
> -#define PM8901_SUBTYPE 0x0f
> -#define PM8950_SUBTYPE 0x10
> -#define PMI8950_SUBTYPE 0x11
> -#define PM8998_SUBTYPE 0x14
> -#define PMI8998_SUBTYPE 0x15
> -#define PM8005_SUBTYPE 0x18
> -#define PM660L_SUBTYPE 0x1A
> -#define PM660_SUBTYPE 0x1B
> -#define PM8150_SUBTYPE 0x1E
> -#define PM8150L_SUBTYPE 0x1f
> -#define PM8150B_SUBTYPE 0x20
> -#define PMK8002_SUBTYPE 0x21
> -#define PM8009_SUBTYPE 0x24
> -#define PM8150C_SUBTYPE 0x26
> -#define SMB2351_SUBTYPE 0x29
> -
> static const struct of_device_id pmic_spmi_id_table[] = {
> { .compatible = "qcom,pm660", .data = (void *)PM660_SUBTYPE },
> { .compatible = "qcom,pm660l", .data = (void *)PM660L_SUBTYPE },
> @@ -81,57 +55,64 @@ static const struct of_device_id pmic_spmi_id_table[] = {
> { }
> };
>
> -static void pmic_spmi_show_revid(struct regmap *map, struct device *dev)
> +static void pmic_spmi_load_revid(struct regmap *map, struct device *dev,
> + struct qcom_spmi_pmic *pmic)
> {
> - unsigned int rev2, minor, major, type, subtype;
> - const char *name = "unknown";
> int ret, i;
>
> - ret = regmap_read(map, PMIC_TYPE, &type);
> + ret = regmap_read(map, PMIC_TYPE, &pmic->type);

Given this isn't just for a debug print any more, I'd suggest you should
do proper error handling. If these values can't be read fail the probe.

> if (ret < 0)
> return;
>
> - if (type != PMIC_TYPE_VALUE)
> + if (pmic->type != PMIC_TYPE_VALUE)
> return;
>
> - ret = regmap_read(map, PMIC_SUBTYPE, &subtype);
> + ret = regmap_read(map, PMIC_SUBTYPE, &pmic->subtype);
> if (ret < 0)
> return;
>
> for (i = 0; i < ARRAY_SIZE(pmic_spmi_id_table); i++) {
> - if (subtype == (unsigned long)pmic_spmi_id_table[i].data)
> + if (pmic->subtype == (unsigned long)pmic_spmi_id_table[i].data)
> break;
> }
>
> - if (i != ARRAY_SIZE(pmic_spmi_id_table))
> - name = pmic_spmi_id_table[i].compatible;
> + if (i != ARRAY_SIZE(pmic_spmi_id_table)) {
> + pmic->name = kmalloc(strlen(pmic_spmi_id_table[i].compatible),
> + GFP_KERNEL);
> + strncpy(pmic->name, pmic_spmi_id_table[i].compatible,
> + strlen(pmic_spmi_id_table[i].compatible));

Under what circumstances could you not just use a pointer to the string in the
table for this? Is there a life time issue? Given you free the string in the
remove it seems unlikely.

If so why not use use kstrdup()

> + }
>
> - ret = regmap_read(map, PMIC_REV2, &rev2);
> + ret = regmap_read(map, PMIC_REV2, &pmic->rev2);
> if (ret < 0)
> return;
>
> - ret = regmap_read(map, PMIC_REV3, &minor);
> + ret = regmap_read(map, PMIC_REV3, &pmic->minor);
> if (ret < 0)
> return;
>
> - ret = regmap_read(map, PMIC_REV4, &major);
> + ret = regmap_read(map, PMIC_REV4, &pmic->major);
> if (ret < 0)
> return;
>
> + if (pmic->subtype == PMI8998_SUBTYPE || pmic->subtype == PM660_SUBTYPE) {
> + ret = regmap_read(map, PMIC_FAB_ID, &pmic->fab_id);
> + if (ret < 0)
> + return;
> + }
> +
> /*
> * In early versions of PM8941 and PM8226, the major revision number
> * started incrementing from 0 (eg 0 = v1.0, 1 = v2.0).
> * Increment the major revision number here if the chip is an early
> * version of PM8941 or PM8226.
> */
> - if ((subtype == PM8941_SUBTYPE || subtype == PM8226_SUBTYPE) &&
> - major < 0x02)
> - major++;
> -
> - if (subtype == PM8110_SUBTYPE)
> - minor = rev2;
> + if ((pmic->subtype == PM8941_SUBTYPE || pmic->subtype == PM8226_SUBTYPE) &&
> + pmic->major < 0x02)
> + pmic->major++;
>
> - dev_dbg(dev, "%x: %s v%d.%d\n", subtype, name, major, minor);
> + if (pmic->subtype == PM8110_SUBTYPE)
> + pmic->minor = pmic->rev2;
> }
>
> static const struct regmap_config spmi_regmap_config = {
> @@ -144,22 +125,38 @@ static const struct regmap_config spmi_regmap_config = {
> static int pmic_spmi_probe(struct spmi_device *sdev)
> {
> struct regmap *regmap;
> + struct qcom_spmi_pmic *pmic;
>
> regmap = devm_regmap_init_spmi_ext(sdev, &spmi_regmap_config);
> if (IS_ERR(regmap))
> return PTR_ERR(regmap);
>
> + pmic = devm_kzalloc(&sdev->dev, sizeof(*pmic), GFP_KERNEL);
> + if (!pmic)
> + return -ENOMEM;
> +
> /* Only the first slave id for a PMIC contains this information */
> - if (sdev->usid % 2 == 0)
> - pmic_spmi_show_revid(regmap, &sdev->dev);
> + if (sdev->usid % 2 == 0) {
> + pmic_spmi_load_revid(regmap, &sdev->dev, pmic);
> + spmi_device_set_drvdata(sdev, pmic);
> + qcom_pmic_print_info(&sdev->dev, pmic);
> + }
>
> return devm_of_platform_populate(&sdev->dev);
> }
>
> +static void pmic_spmi_remove(struct spmi_device *sdev)
> +{
> + struct qcom_spmi_pmic *pmic = spmi_device_get_drvdata(sdev);
> +
> + kfree(pmic->name);
> +}
> +
> MODULE_DEVICE_TABLE(of, pmic_spmi_id_table);
>
> static struct spmi_driver pmic_spmi_driver = {
> .probe = pmic_spmi_probe,
> + .remove = pmic_spmi_remove,
> .driver = {
> .name = "pmic-spmi",
> .of_match_table = pmic_spmi_id_table,
> diff --git a/include/soc/qcom/qcom-pmic.h b/include/soc/qcom/qcom-pmic.h
> new file mode 100644
> index 000000000000..bf87a4f2de6a
> --- /dev/null
> +++ b/include/soc/qcom/qcom-pmic.h
> @@ -0,0 +1,58 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/* Copyright (c) 2021 Linaro. All rights reserved.
> + * Copyright (c) 2021 Caleb Connolly <caleb.connolly@linaro.org>
> + */
> +
> +#define COMMON_SUBTYPE 0x00
> +#define PM8941_SUBTYPE 0x01
> +#define PM8841_SUBTYPE 0x02
> +#define PM8019_SUBTYPE 0x03
> +#define PM8226_SUBTYPE 0x04
> +#define PM8110_SUBTYPE 0x05
> +#define PMA8084_SUBTYPE 0x06
> +#define PMI8962_SUBTYPE 0x07
> +#define PMD9635_SUBTYPE 0x08
> +#define PM8994_SUBTYPE 0x09
> +#define PMI8994_SUBTYPE 0x0a
> +#define PM8916_SUBTYPE 0x0b
> +#define PM8004_SUBTYPE 0x0c
> +#define PM8909_SUBTYPE 0x0d
> +#define PM8028_SUBTYPE 0x0e
> +#define PM8901_SUBTYPE 0x0f
> +#define PM8950_SUBTYPE 0x10
> +#define PMI8950_SUBTYPE 0x11
> +#define PM8998_SUBTYPE 0x14
> +#define PMI8998_SUBTYPE 0x15
> +#define PM8005_SUBTYPE 0x18
> +#define PM660L_SUBTYPE 0x1A
> +#define PM660_SUBTYPE 0x1B
> +#define PM8150_SUBTYPE 0x1E
> +#define PM8150L_SUBTYPE 0x1f
> +#define PM8150B_SUBTYPE 0x20
> +#define PMK8002_SUBTYPE 0x21
> +#define PM8009_SUBTYPE 0x24
> +#define PM8150C_SUBTYPE 0x26
> +#define SMB2351_SUBTYPE 0x29
> +
> +#define PMI8998_FAB_ID_SMIC 0x11
> +#define PMI8998_FAB_ID_GF 0x30
> +
> +#define PM660_FAB_ID_GF 0x0
> +#define PM660_FAB_ID_TSMC 0x2
> +#define PM660_FAB_ID_MX 0x3
> +
> +struct qcom_spmi_pmic {
> + unsigned int type;
> + unsigned int subtype;
> + unsigned int major;
> + unsigned int minor;
> + unsigned int rev2;
> + unsigned int fab_id;
> + char *name;
> +};
> +
> +inline void qcom_pmic_print_info(struct device *dev, struct qcom_spmi_pmic *pmic)
> +{
> + dev_info(dev, "%x: %s v%d.%d\n",
> + pmic->subtype, pmic->name, pmic->major, pmic->minor);
> +}