Re: [PATCH v9 1/5] mfd: mxs-lradc: Add support for mxs-lradc MFD

From: Marek Vasut
Date: Tue Nov 15 2016 - 12:45:42 EST


On 11/15/2016 06:06 PM, Ksenija StanojeviÄ wrote:
> On Mon, Nov 14, 2016 at 7:43 PM, Marek Vasut <marex@xxxxxxx> wrote:
>> On 11/02/2016 08:38 AM, Ksenija Stanojevic wrote:
>>> Add core files for low resolution analog-to-digital converter (mxs-lradc)
>>> MFD driver.
>>>
>>> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
>>> ---
>>> Changes in v9:
>>> - improve commit message.
>>>
>>> Changes in v8:
>>> - rebase onto 4.9-rc1
>>>
>>> Changes in v7:
>>> - define macros ADC_CELL and TSC_CELL
>>> - remove one cell and dynamically set them in the switch()
>>> - fail in the touchscreen driver instead of mfd driver if
>>> hardware doesn't contain a touchscreen
>>>
>>> Changes in v6:
>>> - update copyright
>>> - add kernel-doc header for struct mxs-lradc
>>> - add error message
>>> - change EINVAL to ENODEV
>>> - use PLATFORM_DEVID_NONE instead -1
>>> - cosmetic fixes
>>>
>>> Changes in v5:
>>> - use DEFINE_RES_MEM
>>> - don't pass ioreammaped adress to platform cells
>>> - move comment outside of struct mxs_lradc
>>> - change type of argument in mxs_lradc_reg_set, mxs_lradc_reg_clear,
>>> mxs_lradc_reg_wrt (struct mxs_lradc * -> void __iomem *)
>>>
>>> Changes in v4:
>>> - update copyright
>>> - use DEFINE_RES_IRQ_NAMED
>>> - remove mxs_lradc_add_device function
>>> - use struct mfd_cell in static form
>>> - improve spacing
>>> - remove unnecessary comment
>>> - remove platform_get_irq
>>> - remove touch_ret and use ret instead
>>> - rename use_touchscreen to touchscreen_wire
>>> - use goto statements
>>> - remove irq[13], irq_count and irq_name from struct mxs_lradc
>>> - remove all defines from inside the struct definition
>>>
>>> Changes in v3:
>>> - add note to commit message
>>> - move switch statement into if(touch_ret == 0) branch
>>> - add MODULE_AUTHOR
>>>
>>> Changes in v2:
>>> - do not change spacing in Kconfig
>>> - make struct mfd_cell part of struct mxs_lradc
>>> - use switch instead of if in mxs_lradc_irq_mask
>>> - use only necessary header files in mxs_lradc.h
>>> - use devm_mfd_add_device
>>> - use separate function to register mfd device
>>> - change licence to GPL
>>> - add copyright
>>>
>>> drivers/mfd/Kconfig | 17 +++
>>> drivers/mfd/Makefile | 1 +
>>> drivers/mfd/mxs-lradc.c | 249 ++++++++++++++++++++++++++++++++++++++++++
>>> include/linux/mfd/mxs-lradc.h | 203 ++++++++++++++++++++++++++++++++++
>>> 4 files changed, 470 insertions(+)
>>> create mode 100644 drivers/mfd/mxs-lradc.c
>>> create mode 100644 include/linux/mfd/mxs-lradc.h
>>>
>>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
>>> index c6df644..bdd88cf 100644
>>> --- a/drivers/mfd/Kconfig
>>> +++ b/drivers/mfd/Kconfig
>>> @@ -326,6 +326,23 @@ config MFD_MC13XXX_I2C
>>> help
>>> Select this if your MC13xxx is connected via an I2C bus.
>>>
>>> +config MFD_MXS_LRADC
>>> + tristate "Freescale i.MX23/i.MX28 LRADC"
>>> + depends on ARCH_MXS || COMPILE_TEST
>>> + select MFD_CORE
>>> + select STMP_DEVICE
>>> + help
>>> + Say yes here to build support for the Low Resolution
>>> + Analog-to-Digital Converter (LRADC) found on the i.MX23 and i.MX28
>>> + processors. This driver provides common support for accessing the
>>> + device, additional drivers must be enabled in order to use the
>>> + functionality of the device:
>>> + mxs-lradc-adc for ADC readings
>>> + mxs-lradc-ts for touchscreen support
>>> +
>>> + This driver can also be built as a module. If so, the module will be
>>> + called mxs-lradc.
>>> +
>>> config MFD_MX25_TSADC
>>> tristate "Freescale i.MX25 integrated Touchscreen and ADC unit"
>>> select REGMAP_MMIO
>>> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
>>> index 9834e66..057ca15 100644
>>> --- a/drivers/mfd/Makefile
>>> +++ b/drivers/mfd/Makefile
>>> @@ -211,3 +211,4 @@ obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o
>>> obj-$(CONFIG_MFD_MT6397) += mt6397-core.o
>>>
>>> obj-$(CONFIG_MFD_ALTERA_A10SR) += altera-a10sr.o
>>> +obj-$(CONFIG_MFD_MXS_LRADC) += mxs-lradc.o
>>> diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
>>> new file mode 100644
>>> index 0000000..ffc8f2e
>>> --- /dev/null
>>> +++ b/drivers/mfd/mxs-lradc.c
>>> @@ -0,0 +1,249 @@
>>> +/*
>>> + * Freescale MXS Low Resolution Analog-to-Digital Converter driver
>>> + *
>>> + * Copyright (c) 2012 DENX Software Engineering, GmbH.
>>> + * Copyright (c) 2016 Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
>>> + *
>>> + * Authors:
>>> + * Marek Vasut <marex@xxxxxxx>
>>> + * Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
>>> + *
>>> + * 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/clk.h>
>>> +#include <linux/device.h>
>>> +#include <linux/mfd/core.h>
>>> +#include <linux/mfd/mxs-lradc.h>
>>> +#include <linux/module.h>
>>> +#include <linux/of.h>
>>> +#include <linux/of_device.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/slab.h>
>>> +
>>> +#define MXS_LRADC_BASE 0x80050000
>>
>> Just for my understanding, why is this hardware address hard-coded here?
>> Shouldn't that be fetched from DT ?
>
> Do you mean that address should be fetched by using of_address_to_resource()
> in probe function, or something else?

Probably platform_get_resource() .

--
Best regards,
Marek Vasut