RE: [PATCH 3/3] soc: fsl: add RCPM driver

[Ran Wang]

Hi Dongsheng,

On 2018/9/5 10:58, Dongsheng Wang wrote:
> 
> Please change your comments style.
> 
> On 2018/8/31 11:56, Ran Wang wrote:
> > The NXP's QorIQ Processors based on ARM Core have RCPM module (Run
> > Control and Power Management), which performs all device-level tasks
> > associated with power management such as wakeup source control.
> >
> > This driver depends on FSL platform PM driver framework which help to
> > isolate user and PM service provider (such as RCPM driver).
> >
> > Signed-off-by: Chenhui Zhao <chenhui.zhao@xxxxxxx>
> > Signed-off-by: Ying Zhang <ying.zhang22455@xxxxxxx>
> > Signed-off-by: Ran Wang <ran.wang_1@xxxxxxx>
> > ---
> >  drivers/soc/fsl/Kconfig   |    6 ++
> >  drivers/soc/fsl/Makefile  |    1 +
> >  drivers/soc/fsl/ls-rcpm.c |  153
> > +++++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 160 insertions(+), 0 deletions(-)  create mode
> > 100644 drivers/soc/fsl/ls-rcpm.c
> >
> > diff --git a/drivers/soc/fsl/Kconfig b/drivers/soc/fsl/Kconfig index
> > 6517412..882330d 100644
> > --- a/drivers/soc/fsl/Kconfig
> > +++ b/drivers/soc/fsl/Kconfig
> > @@ -30,3 +30,9 @@ config FSL_PLAT_PM
> >  	  have to know the implement details of wakeup function it require.
> >  	  Besides, it is also easy for service side to upgrade its logic when
> >  	  design changed and remain user side unchanged.
> > +
> > +config LS_RCPM
> > +	bool "Freescale RCPM support"
> > +	depends on (FSL_PLAT_PM)
> > +	help
> > +	  This feature is to enable specified wakeup source for system sleep.
> > diff --git a/drivers/soc/fsl/Makefile b/drivers/soc/fsl/Makefile index
> > 8f9db23..43ff71a 100644
> > --- a/drivers/soc/fsl/Makefile
> > +++ b/drivers/soc/fsl/Makefile
> > @@ -7,3 +7,4 @@ obj-$(CONFIG_QUICC_ENGINE)		+= qe/
> >  obj-$(CONFIG_CPM)			+= qe/
> >  obj-$(CONFIG_FSL_GUTS)			+= guts.o
> >  obj-$(CONFIG_FSL_PLAT_PM)	+= plat_pm.o
> > +obj-$(CONFIG_LS_RCPM)		+= ls-rcpm.o
> > diff --git a/drivers/soc/fsl/ls-rcpm.c b/drivers/soc/fsl/ls-rcpm.c new
> > file mode 100644 index 0000000..b0feb88
> > --- /dev/null
> > +++ b/drivers/soc/fsl/ls-rcpm.c
> > @@ -0,0 +1,153 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +//
> > +// plat_pm.c - Freescale Layerscape RCPM driver // // Copyright 2018
> > +NXP // // Author: Ran Wang <ran.wang_1@xxxxxxx>,
> > +
> > +#include <linux/init.h>
> > +#include <linux/module.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/of_address.h>
> > +#include <linux/slab.h>
> > +#include <soc/fsl/plat_pm.h>
> > +
> > +#define MAX_COMPATIBLE_NUM	10
> > +
> > +struct rcpm_t {
> > +	struct device *dev;
> > +	void __iomem *ippdexpcr_addr;
> > +	bool big_endian;	/* Big/Little endian of RCPM module */
> > +};
> > +
> > +// rcpm_handle - Configure RCPM reg according to wake up source
> > +request // @user_dev: pointer to user's device struct // @flag: to
> > +enable(true) or disable(false) wakeup source // @handle_priv: pointer
> > +to struct rcpm_t instance // // Return 0 on success other negative
> > +errno static int rcpm_handle(struct device *user_dev, bool flag, void
> > +*handle_priv) {
> > +	struct rcpm_t *rcpm;
> > +	bool big_endian;
> > +	const char  *dev_compatible_array[MAX_COMPATIBLE_NUM];
> > +	void __iomem *ippdexpcr_addr;
> > +	u32 ippdexpcr;
> > +	u32 set_bit;
> > +	int ret, num, i;
> > +
> > +	rcpm = handle_priv;
> > +	big_endian = rcpm->big_endian;
> > +	ippdexpcr_addr = rcpm->ippdexpcr_addr;
> > +
> > +	num = device_property_read_string_array(user_dev, "compatible",
> > +			dev_compatible_array, MAX_COMPATIBLE_NUM);
> > +	if (num < 0)
> > +		return num;
> > +
> > +	for (i = 0; i < num; i++) {
> > +		if (!device_property_present(rcpm->dev,
> > +					dev_compatible_array[i]))
> > +			continue;
> > +		else {
> Remove this else.

Got it! Will update in next version.

> > +			ret = device_property_read_u32(rcpm->dev,
> > +					dev_compatible_array[i], &set_bit);
> > +			if (ret)
> > +				return ret;
> > +
> > +			if (!device_property_present(rcpm->dev,
> > +						dev_compatible_array[i]))
> This has been checked. Continue ? or return ENODEV？

Yes, this checking is not necessary, will remove in next version

> > +				return -ENODEV;
> > +			else {
> Remove this else.

OK

> > +				ret = device_property_read_u32(rcpm->dev,
> > +						dev_compatible_array[i],
> &set_bit);
> > +				if (ret)
> > +					return ret;
> > +
> > +				if (big_endian)
> > +					ippdexpcr =
> ioread32be(ippdexpcr_addr);
> > +				else
> > +					ippdexpcr =
> ioread32(ippdexpcr_addr);
> > +
> > +				if (flag)
> > +					ippdexpcr |= set_bit;
> > +				else
> > +					ippdexpcr &= ~set_bit;
> > +
> > +				if (big_endian) {
> > +					iowrite32be(ippdexpcr,
> ippdexpcr_addr);
> > +					ippdexpcr =
> ioread32be(ippdexpcr_addr);
> > +				} else
> if (x) {
> ....
> ....
> }  else {
> 
> }

Got it!

> > +					iowrite32(ippdexpcr, ippdexpcr_addr);
> > +
> > +				return 0;
> > +			}
> > +		}
> > +	}
> > +
> > +	return -ENODEV;
> > +}
> > +
> > +static int ls_rcpm_probe(struct platform_device *pdev) {
> > +	struct resource *r;
> > +	struct rcpm_t *rcpm;
> > +
> > +	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!r)
> > +		return -ENODEV;
> > +
> > +	rcpm = kmalloc(sizeof(*rcpm), GFP_KERNEL);
> kzalloc is better.

OK

> > +	if (!rcpm)
> > +		return -ENOMEM;
> > +
> > +	rcpm->big_endian = device_property_read_bool(&pdev->dev,
> > +"big-endian");
> > +
> > +	rcpm->ippdexpcr_addr = devm_ioremap_resource(&pdev->dev, r);
> > +	if (IS_ERR(rcpm->ippdexpcr_addr))
> > +		return PTR_ERR(rcpm->ippdexpcr_addr);
> > +
> > +	rcpm->dev = &pdev->dev;
> > +	platform_set_drvdata(pdev, rcpm);
> > +
> > +	return register_fsl_platform_wakeup_source(rcpm_handle, rcpm); }
> > +
> > +static int ls_rcpm_remove(struct platform_device *pdev) {
> > +	struct rcpm_t	*rcpm;
> Not need a table.

OK, thanks for your careful review.

Regards,
Ran
 

> Cheers,
> -Dongsheng
> 
> > +
> > +	rcpm = platform_get_drvdata(pdev);
> > +	deregister_fsl_platform_wakeup_source(rcpm);
> > +	kfree(rcpm);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct of_device_id ls_rcpm_of_match[] = {
> > +	{ .compatible = "fsl,qoriq-rcpm-2.1", },
> > +	{}
> > +};
> > +MODULE_DEVICE_TABLE(of, ls_rcpm_of_match);
> > +
> > +static struct platform_driver ls_rcpm_driver = {
> > +	.driver = {
> > +		.name = "ls-rcpm",
> > +		.of_match_table = ls_rcpm_of_match,
> > +	},
> > +	.probe = ls_rcpm_probe,
> > +	.remove = ls_rcpm_remove,
> > +};
> > +
> > +static int __init ls_rcpm_init(void)
> > +{
> > +	return platform_driver_register(&ls_rcpm_driver);
> > +}
> > +subsys_initcall(ls_rcpm_init);
> > +
> > +static void __exit ls_rcpm_exit(void) {
> > +	platform_driver_unregister(&ls_rcpm_driver);
> > +}
> > +module_exit(ls_rcpm_exit);
>