On 05/29/2018 09:55 AM, Lee Jones wrote: > On Thu, 24 May 2018, Steve Twiss wrote: > >> Thanks Marek, >> >> On 23 May 2018 12:42 Marek Vasut wrote, >> >>> To: linux-kernel@xxxxxxxxxxxxxxx >>> Cc: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>; Geert Uytterhoeven <geert+renesas@xxxxxxxxx>; Lee Jones <lee.jones@xxxxxxxxxx>; Mark Brown <broonie@xxxxxxxxxx>; Steve Twiss <stwiss.opensource@xxxxxxxxxxx>; Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>; linux-renesas-soc@xxxxxxxxxxxxxxx >>> Subject: [PATCH 4/6] mfd: da9063: Disallow RTC on DA9063L >>> >>> The DA9063L does not contain RTC block, unlike the full DA9063. >>> Do not allow binding RTC driver on this variant of the chip. >>> >>> Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx> >>> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> >>> Cc: Lee Jones <lee.jones@xxxxxxxxxx> >>> Cc: Mark Brown <broonie@xxxxxxxxxx> >>> Cc: Steve Twiss <stwiss.opensource@xxxxxxxxxxx> >>> Cc: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> >>> Cc: linux-renesas-soc@xxxxxxxxxxxxxxx >>> --- >>> drivers/mfd/da9063-core.c | 18 +++++++++++------- >>> 1 file changed, 11 insertions(+), 7 deletions(-) >>> >>> diff --git a/drivers/mfd/da9063-core.c b/drivers/mfd/da9063-core.c index 7360b76b4f72..263c83006413 100644 >>> --- a/drivers/mfd/da9063-core.c >>> +++ b/drivers/mfd/da9063-core.c >>> @@ -101,14 +101,14 @@ static const struct mfd_cell da9063_devs[] = { >>> .of_compatible = "dlg,da9063-onkey", >>> }, >>> { >>> + .name = DA9063_DRVNAME_VIBRATION, >>> + }, >>> + { /* Only present on DA9063 , not on DA9063L */ >>> .name = DA9063_DRVNAME_RTC, >>> .num_resources = ARRAY_SIZE(da9063_rtc_resources), >>> .resources = da9063_rtc_resources, >>> .of_compatible = "dlg,da9063-rtc", >>> }, >>> - { >>> - .name = DA9063_DRVNAME_VIBRATION, >>> - }, >>> }; >>> >>> static int da9063_clear_fault_log(struct da9063 *da9063) @@ -163,7 +163,7 @@ int da9063_device_init(struct da9063 *da9063, unsigned int irq) { >>> struct da9063_pdata *pdata = da9063->dev->platform_data; >>> int model, variant_id, variant_code; >>> - int ret; >>> + int da9063_devs_len, ret; >>> >>> ret = da9063_clear_fault_log(da9063); >>> if (ret < 0) >>> @@ -225,9 +225,13 @@ int da9063_device_init(struct da9063 *da9063, unsigned int irq) >>> >>> da9063->irq_base = regmap_irq_chip_get_base(da9063->regmap_irq); >>> >>> - ret = mfd_add_devices(da9063->dev, -1, da9063_devs, >>> - ARRAY_SIZE(da9063_devs), NULL, da9063->irq_base, >>> - NULL); >>> + da9063_devs_len = ARRAY_SIZE(da9063_devs); >>> + /* RTC, the last device in the list, is only present on DA9063 */ >>> + if (da9063->type == PMIC_TYPE_DA9063L) >>> + da9063_devs_len -= 1; >>> + >>> + ret = mfd_add_devices(da9063->dev, -1, da9063_devs, da9063_devs_len, >>> + NULL, da9063->irq_base, NULL); >>> if (ret) >>> dev_err(da9063->dev, "Cannot add MFD cells\n"); >>> >> >> MFD cells definitely has less impact than regmap_range and regmap_irq. >> I agree, there's no point in having a completely new >> static const struct mfd_cell da9063l_devs[] = { ... } for DA9063L > > This solution is fragile. > > I agree that a new MFD cell is not required in its entirety. It > would however, be better to split out the RTC entry into a new one and > only register it when (da9063->type == PMIC_TYPE_DA9063). This is a > better solution than messing around with passed struct sizes. This indeed is better. btw this da9063_device_init() function is missing a failpath to undo the setup done by da9063_irq_init(), so I'll be sending a patch for that too shortly. -- Best regards, Marek Vasut