Re: [PATCH v3 2/2] mmc: pwrseq: add support for Marvell SD8787 chip

[Matt Ranostay <matt@ranostay.consulting>]

On Sun, Jan 15, 2017 at 6:35 PM, Shawn Lin <shawn.lin@rock-chips.com> wrote:
> On 2017/1/16 5:41, Matt Ranostay wrote:
>>
>> On Thu, Jan 12, 2017 at 11:16 PM, Shawn Lin <shawn.lin@rock-chips.com>
>> wrote:
>>>
>>> On 2017/1/13 13:29, Matt Ranostay wrote:
>>>>
>>>>
>>>> Allow power sequencing for the Marvell SD8787 Wifi/BT chip.
>>>> This can be abstracted to other chipsets if needed in the future.
>>>>
>>>> Cc: Tony Lindgren <tony@atomide.com>
>>>> Cc: Ulf Hansson <ulf.hansson@linaro.org>
>>>> Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
>>>> ---
>>>>  drivers/mmc/core/Kconfig         |  10 ++++
>>>>  drivers/mmc/core/Makefile        |   1 +
>>>>  drivers/mmc/core/pwrseq_sd8787.c | 117
>>>> +++++++++++++++++++++++++++++++++++++++
>>>>  3 files changed, 128 insertions(+)
>>>>  create mode 100644 drivers/mmc/core/pwrseq_sd8787.c
>>>>
>>>> diff --git a/drivers/mmc/core/Kconfig b/drivers/mmc/core/Kconfig
>>>> index cdfa8520a4b1..fc1ecdaaa9ca 100644
>>>> --- a/drivers/mmc/core/Kconfig
>>>> +++ b/drivers/mmc/core/Kconfig
>>>> @@ -12,6 +12,16 @@ config PWRSEQ_EMMC
>>>>           This driver can also be built as a module. If so, the module
>>>>           will be called pwrseq_emmc.
>>>>
>>>> +config PWRSEQ_SD8787
>>>> +       tristate "HW reset support for SD8787 BT + Wifi module"
>>>> +       depends on OF && (MWIFIEX || BT_MRVL_SDIO)
>>>> +       help
>>>> +         This selects hardware reset support for the SD8787 BT + Wifi
>>>> +         module. By default this option is set to n.
>>>> +
>>>> +         This driver can also be built as a module. If so, the module
>>>> +         will be called pwrseq_sd8787.
>>>> +
>>>
>>>
>>>
>>> I don't like this way, as we have a chance to list lots
>>> configure options here. wifi A,B,C,D...Z, all of them need a
>>> new section here if needed?
>>>
>>> Instead, could you just extent pwrseq_simple.c and add you
>>> .compatible = "mmc-pwrseq-sd8787", "mmc-pwrseq-simple"?
>>
>>
>> You mean all the chipset pwrseqs linked into the pwrseq-simple module?
>
>
> What I mean was if you just extent the pwrseq-simple a bit, you could
> just add your chipset pwrseqs linked into the pwrseq-simple. But if you
> need a different *pattern* of pwrseqs, you should need a new name, for
> instance, pwrseq-sdio.c etc... But please don't use the name of
> sd8787? So if I use a wifi named ABC but using the same pwrseq pattenr,
> should I include your "mmc-pwrseq- sd8787" for that or I need a new
> mmc-pwrseq-ABC.c?

Ah so pwrseq-sdio.c seems reasonable and having chipsets functions
defined in a structure. That could be abstracted out for other
chipsets that could needed in the future.

- Matt

>
>
>>
>> Ulf your thoughts on this?
>>
>>>
>>>
>>>
>>>>  config PWRSEQ_SIMPLE
>>>>         tristate "Simple HW reset support for MMC"
>>>>         default y
>>>> diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
>>>> index b2a257dc644f..0f81464fa824 100644
>>>> --- a/drivers/mmc/core/Makefile
>>>> +++ b/drivers/mmc/core/Makefile
>>>> @@ -10,6 +10,7 @@ mmc_core-y                    := core.o bus.o host.o \
>>>>                                    quirks.o slot-gpio.o
>>>>  mmc_core-$(CONFIG_OF)          += pwrseq.o
>>>>  obj-$(CONFIG_PWRSEQ_SIMPLE)    += pwrseq_simple.o
>>>> +obj-$(CONFIG_PWRSEQ_SD8787)    += pwrseq_sd8787.o
>>>>  obj-$(CONFIG_PWRSEQ_EMMC)      += pwrseq_emmc.o
>>>>  mmc_core-$(CONFIG_DEBUG_FS)    += debugfs.o
>>>>  obj-$(CONFIG_MMC_BLOCK)                += mmc_block.o
>>>> diff --git a/drivers/mmc/core/pwrseq_sd8787.c
>>>> b/drivers/mmc/core/pwrseq_sd8787.c
>>>> new file mode 100644
>>>> index 000000000000..f4080fe6439e
>>>> --- /dev/null
>>>> +++ b/drivers/mmc/core/pwrseq_sd8787.c
>>>> @@ -0,0 +1,117 @@
>>>> +/*
>>>> + * pwrseq_sd8787.c - power sequence support for Marvell SD8787 BT +
>>>> Wifi
>>>> chip
>>>> + *
>>>> + * Copyright (C) 2016 Matt Ranostay <matt@ranostay.consulting>
>>>> + *
>>>> + * Based on the original work pwrseq_simple.c
>>>> + *  Copyright (C) 2014 Linaro Ltd
>>>> + *  Author: Ulf Hansson <ulf.hansson@linaro.org>
>>>> + *
>>>> + * This program is free software; you can redistribute it and/or modify
>>>> + * it under the terms of the GNU General Public License as published by
>>>> + * the Free Software Foundation; either version 2 of the License, or
>>>> + * (at your option) any later version.
>>>> + *
>>>> + * This program is distributed in the hope that it will be useful,
>>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>>>> + * GNU General Public License for more details.
>>>> + *
>>>> + */
>>>> +
>>>> +#include <linux/delay.h>
>>>> +#include <linux/init.h>
>>>> +#include <linux/kernel.h>
>>>> +#include <linux/platform_device.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/slab.h>
>>>> +#include <linux/device.h>
>>>> +#include <linux/err.h>
>>>> +#include <linux/gpio/consumer.h>
>>>> +
>>>> +#include <linux/mmc/host.h>
>>>> +
>>>> +#include "pwrseq.h"
>>>> +
>>>> +struct mmc_pwrseq_sd8787 {
>>>> +       struct mmc_pwrseq pwrseq;
>>>> +       struct gpio_desc *reset_gpio;
>>>> +       struct gpio_desc *pwrdn_gpio;
>>>> +};
>>>> +
>>>> +#define to_pwrseq_sd8787(p) container_of(p, struct mmc_pwrseq_sd8787,
>>>> pwrseq)
>>>> +
>>>> +static void mmc_pwrseq_sd8787_pre_power_on(struct mmc_host *host)
>>>> +{
>>>> +       struct mmc_pwrseq_sd8787 *pwrseq =
>>>> to_pwrseq_sd8787(host->pwrseq);
>>>> +
>>>> +       gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
>>>> +
>>>> +       msleep(300);
>>>> +       gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
>>>> +}
>>>> +
>>>> +static void mmc_pwrseq_sd8787_power_off(struct mmc_host *host)
>>>> +{
>>>> +       struct mmc_pwrseq_sd8787 *pwrseq =
>>>> to_pwrseq_sd8787(host->pwrseq);
>>>> +
>>>> +       gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 0);
>>>> +       gpiod_set_value_cansleep(pwrseq->reset_gpio, 0);
>>>> +}
>>>> +
>>>> +static const struct mmc_pwrseq_ops mmc_pwrseq_sd8787_ops = {
>>>> +       .pre_power_on = mmc_pwrseq_sd8787_pre_power_on,
>>>> +       .power_off = mmc_pwrseq_sd8787_power_off,
>>>> +};
>>>> +
>>>> +static const struct of_device_id mmc_pwrseq_sd8787_of_match[] = {
>>>> +       { .compatible = "mmc-pwrseq-sd8787",},
>>>> +       {/* sentinel */},
>>>> +};
>>>> +MODULE_DEVICE_TABLE(of, mmc_pwrseq_sd8787_of_match);
>>>> +
>>>> +static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
>>>> +{
>>>> +       struct mmc_pwrseq_sd8787 *pwrseq;
>>>> +       struct device *dev = &pdev->dev;
>>>> +
>>>> +       pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
>>>> +       if (!pwrseq)
>>>> +               return -ENOMEM;
>>>> +
>>>> +       pwrseq->pwrdn_gpio = devm_gpiod_get(dev, "pwrdn",
>>>> GPIOD_OUT_LOW);
>>>> +       if (IS_ERR(pwrseq->pwrdn_gpio))
>>>> +               return PTR_ERR(pwrseq->pwrdn_gpio);
>>>> +
>>>> +       pwrseq->reset_gpio = devm_gpiod_get(dev, "reset",
>>>> GPIOD_OUT_LOW);
>>>> +       if (IS_ERR(pwrseq->reset_gpio))
>>>> +               return PTR_ERR(pwrseq->reset_gpio);
>>>> +
>>>> +       pwrseq->pwrseq.dev = dev;
>>>> +       pwrseq->pwrseq.ops = &mmc_pwrseq_sd8787_ops;
>>>> +       pwrseq->pwrseq.owner = THIS_MODULE;
>>>> +       platform_set_drvdata(pdev, pwrseq);
>>>> +
>>>> +       return mmc_pwrseq_register(&pwrseq->pwrseq);
>>>> +}
>>>> +
>>>> +static int mmc_pwrseq_sd8787_remove(struct platform_device *pdev)
>>>> +{
>>>> +       struct mmc_pwrseq_sd8787 *pwrseq = platform_get_drvdata(pdev);
>>>> +
>>>> +       mmc_pwrseq_unregister(&pwrseq->pwrseq);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static struct platform_driver mmc_pwrseq_sd8787_driver = {
>>>> +       .probe = mmc_pwrseq_sd8787_probe,
>>>> +       .remove = mmc_pwrseq_sd8787_remove,
>>>> +       .driver = {
>>>> +               .name = "pwrseq_sd8787",
>>>> +               .of_match_table = mmc_pwrseq_sd8787_of_match,
>>>> +       },
>>>> +};
>>>> +
>>>> +module_platform_driver(mmc_pwrseq_sd8787_driver);
>>>> +MODULE_LICENSE("GPL v2");
>>>>
>>>
>>>
>>> --
>>> Best Regards
>>> Shawn Lin
>>>
>>
>>
>>
>
>
> --
> Best Regards
> Shawn Lin
>