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

[Shawn Lin <shawn.lin@rock-chips.com>]

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?

>
> 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