Alexandre,
On 02/16/2016 04:02 PM, Alexandre Belloni wrote:
> Hi,
>
> On 01/02/2016 at 15:43:22 -0700, Joshua Henderson wrote :
>> This drivers adds support for the PIC32 real time clock and calendar
>> peripheral:
>> - reading and setting time
>> - alarms when connected to an IRQ
>>
>> Signed-off-by: Joshua Henderson <joshua.henderson@xxxxxxxxxxxxx>
>> ---
>> drivers/rtc/Kconfig | 10 ++
>> drivers/rtc/Makefile | 1 +
>> drivers/rtc/rtc-pic32.c | 450 +++++++++++++++++++++++++++++++++++++++++++++++
>
> Nitpick: there are multiple alignment and blank lines issues that you
> can spot using checkpatch --strict.
Thanks. Will address.
>
>> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
>> index 62d61b2..20c9be5 100644
>> --- a/drivers/rtc/Makefile
>> +++ b/drivers/rtc/Makefile
>> @@ -162,3 +162,4 @@ obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o
>> obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
>> obj-$(CONFIG_RTC_DRV_XGENE) += rtc-xgene.o
>> obj-$(CONFIG_RTC_DRV_ZYNQMP) += rtc-zynqmp.o
>> +obj-$(CONFIG_RTC_DRV_PIC32) += rtc-pic32.o
>
> This list has to be ordered alphabetically.
Ack.
>
>> diff --git a/drivers/rtc/rtc-pic32.c b/drivers/rtc/rtc-pic32.c
>> new file mode 100644
>> index 0000000..7c46ccb
>> --- /dev/null
>> +++ b/drivers/rtc/rtc-pic32.c
>> @@ -0,0 +1,450 @@
>> +/*
>> + * PIC32 RTC driver
>> + *
>> + * Joshua Henderson <joshua.henderson@xxxxxxxxxxxxx>
>> + * Copyright (C) 2016 Microchip Technology Inc. All rights reserved.
>> + *
>> + * This program is free software; you can distribute it and/or modify it
>> + * under the terms of the GNU General Public License (Version 2) as
>> + * published by the Free Software Foundation.
>> + *
>
> This specify GPL v2 but you use MODULE_LICENSE("GPL")
Ack.
>
>> + * This program is distributed in the hope 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/init.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/io.h>
>> +#include <linux/slab.h>
>> +#include <linux/clk.h>
>> +#include <linux/rtc.h>
>> +#include <linux/bcd.h>
>> +
>> +#include <asm/mach-pic32/pic32.h>
>> +
>> +#define DRIVER_NAME "pic32-rtc"
>> +
>> +#define PIC32_RTCCON (0x00)
>
> You probably don't need those parenthesis.
Ack.
>
>> +#define PIC32_RTCCON_ON BIT(15)
>> +#define PIC32_RTCCON_SIDL BIT(13)
>> +#define PIC32_RTCCON_RTCCLKSEL (3 << 9)
>> +#define PIC32_RTCCON_RTCCLKON BIT(6)
>> +#define PIC32_RTCCON_RTCWREN BIT(3)
>> +#define PIC32_RTCCON_RTCSYNC BIT(2)
>> +#define PIC32_RTCCON_HALFSEC BIT(1)
>> +#define PIC32_RTCCON_RTCOE BIT(0)
>> +
>> +#define PIC32_RTCALRM (0x10)
>
> ditto
Ack.
>
>> +#define PIC32_RTCALRM_ALRMEN BIT(15)
>> +#define PIC32_RTCALRM_CHIME BIT(14)
>> +#define PIC32_RTCALRM_PIV BIT(13)
>> +#define PIC32_RTCALRM_ALARMSYNC BIT(12)
>> +#define PIC32_RTCALRM_AMASK (0x0F << 8)
>> +#define PIC32_RTCALRM_ARPT (0xFF << 0)
>
> Nit: For those masks, you can use genmask() or directly 0x0F00 and 0xFF
Ack.
>
>> +struct pic32_rtc_dev {
>> + struct rtc_device *rtc;
>> + void __iomem *reg_base;
>> + struct clk *clk;
>> + spinlock_t flags_lock;
>
> flags_lock is unnecessary, it is used only in one function that is
> called only at probe time
Ack.
>
>> + spinlock_t alarm_lock;
>> + int alarm_irq;
>> + bool alarm_clk_enabled;
>> +};
>> +
>
> [...]
>
>> +static int pic32_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
>> +{
>> + struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
>> + void __iomem *base = pdata->reg_base;
>> + unsigned int have_retried = 0;
>> +
>> + clk_enable(pdata->clk);
>> +retry_get_time:
>> + rtc_tm->tm_hour = readb(base + PIC32_RTCHOUR);
>> + rtc_tm->tm_min = readb(base + PIC32_RTCMIN);
>> + rtc_tm->tm_mon = readb(base + PIC32_RTCMON);
>> + rtc_tm->tm_mday = readb(base + PIC32_RTCDAY);
>> + rtc_tm->tm_year = readb(base + PIC32_RTCYEAR);
>> + rtc_tm->tm_sec = readb(base + PIC32_RTCSEC);
>> +
>> + /*
>> + * The only way to work out whether the system was mid-update
>> + * when we read it is to check the second counter, and if it
>> + * is zero, then we re-try the entire read.
>> + */
>> +
>> + if (rtc_tm->tm_sec == 0 && !have_retried) {
>> + have_retried = 1;
>> + goto retry_get_time;
>> + }
>
> Please change that goto in a do while loop.
Ack.
>
>> +
>> + rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
>> + rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
>> + rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
>> + rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
>> + rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
>> + rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
>> +
>> + rtc_tm->tm_year += 100;
>> +
>> + dev_dbg(dev, "read time %04d.%02d.%02d %02d:%02d:%02d\n",
>> + 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
>> + rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
>> +
>> + rtc_tm->tm_mon -= 1;
>
> Maybe you should do that substraction with the assignment the only
> drawback is that it changes the debug output.
I think that's acceptable. Will move.
>
>> +
>> + clk_disable(pdata->clk);
>> + return rtc_valid_tm(rtc_tm);
>> +}
>> +
>
> [...]
>
>> +static int pic32_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
>> +{
>> + struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
>> + struct rtc_time *alm_tm = &alrm->time;
>> + void __iomem *base = pdata->reg_base;
>> + unsigned int alm_en;
>> +
>> + clk_enable(pdata->clk);
>> + alm_tm->tm_sec = readb(base + PIC32_ALRMSEC);
>> + alm_tm->tm_min = readb(base + PIC32_ALRMMIN);
>> + alm_tm->tm_hour = readb(base + PIC32_ALRMHOUR);
>> + alm_tm->tm_mon = readb(base + PIC32_ALRMMON);
>> + alm_tm->tm_mday = readb(base + PIC32_ALRMDAY);
>> + alm_tm->tm_year = readb(base + PIC32_ALRMYEAR);
>> +
>> + alm_en = readb(base + PIC32_RTCALRM);
>> +
>> + alrm->enabled = (alm_en & PIC32_RTCALRM_ALRMEN) ? 1 : 0;
>> +
>> + dev_dbg(dev, "getalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
>> + alm_en,
>> + 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
>> + alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
>> +
>> + alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
>> + alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
>> + alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
>> + alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
>> + alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
>> + alm_tm->tm_mon -= 1;
> You could merge both lines.
Ack.
>
>> + alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
>> +
>> + clk_disable(pdata->clk);
>> + return 0;
>> +}
>> +
>> +static int pic32_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
>> +{
>> + struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
>> + struct rtc_time *tm = &alrm->time;
>> + void __iomem *base = pdata->reg_base;
>> +
>> + clk_enable(pdata->clk);
>> + dev_dbg(dev, "setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
>> + alrm->enabled,
>> + 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
>> + tm->tm_hour, tm->tm_min, tm->tm_sec);
>> +
>> + writel(0x00, base + PIC32_ALRMTIME);
>> + writel(0x00, base + PIC32_ALRMDATE);
>> +
>> + if (tm->tm_sec < 60 && tm->tm_sec >= 0)
>> + writeb(bin2bcd(tm->tm_sec), base + PIC32_ALRMSEC);
>> +
>> + if (tm->tm_min < 60 && tm->tm_min >= 0)
>> + writeb(bin2bcd(tm->tm_min), base + PIC32_ALRMMIN);
>> +
>> + if (tm->tm_hour < 24 && tm->tm_hour >= 0)
>> + writeb(bin2bcd(tm->tm_hour), base + PIC32_ALRMHOUR);
>> +
>
> Those three tests are unnecessary because rtc_valid_tm() is called
> before ops->set_alarm.
Good catch. Ack.
>
>> + pic32_rtc_setaie(dev, alrm->enabled);
>> +
>> + clk_disable(pdata->clk);
>> + return 0;
>> +}
>> +
>
> [...]
>
>
>> + pic32_rtc_gettime(&pdev->dev, &rtc_tm);
>> +
>> + if (rtc_valid_tm(&rtc_tm)) {
>> + rtc_tm.tm_year = 100;
>> + rtc_tm.tm_mon = 0;
>> + rtc_tm.tm_mday = 1;
>> + rtc_tm.tm_hour = 0;
>> + rtc_tm.tm_min = 0;
>> + rtc_tm.tm_sec = 0;
>> +
>> + pic32_rtc_settime(NULL, &rtc_tm);
>> +
>> + dev_warn(&pdev->dev,
>> + "warning: invalid RTC value so initializing it\n");
>
> This is a bad idea. If you do that, userspace has no way of knowing
> whether the date is valid or not.
Ack.
>
> [...]
>
>> +static const struct of_device_id pic32_rtc_dt_ids[] = {
>> + { .compatible = "microchip,pic32mzda-rtc" },
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, pic32_rtc_dt_ids);
>
> This compatible string needs to be documented. Was that patch 1/2?
It was indeed patch 1/2. I'll make sure you are copied on it next time.
>
>> +
>> +static struct platform_driver pic32_rtc_driver = {
>> + .probe = pic32_rtc_probe,
>> + .remove = pic32_rtc_remove,
>> + .driver = {
>> + .name = DRIVER_NAME,
>> + .owner = THIS_MODULE,
>> + .of_match_table = of_match_ptr(pic32_rtc_dt_ids),
>> + },
>> +};
>> +module_platform_driver(pic32_rtc_driver);
>> +
>> +MODULE_DESCRIPTION("Microchip PIC32 RTC Driver");
>> +MODULE_AUTHOR("Joshua Henderson <joshua.henderson@xxxxxxxxxxxxx>");
>> +MODULE_LICENSE("GPL");
>> +MODULE_ALIAS("platform:" DRIVER_NAME);
>
> I think this driver is DT only, you can get rid of MODULE_ALIAS and
> DRIVER_NAME
Ack.
Thanks,
Josh
