Re: [PATCH] Input: hp_sdc_rtc - remove dead chardev code

From: Geert Uytterhoeven
Date: Thu Nov 14 2019 - 04:47:00 EST


CC linux-m68k

On Thu, Oct 24, 2019 at 3:48 PM Helge Deller <deller@xxxxxx> wrote:
> On 23.10.19 17:22, Alexandre Belloni wrote:
> > On 23/10/2019 16:25:02+0200, Arnd Bergmann wrote:
> >> The driver contains half of the implementation of /dev/rtc, but this
> >> was never completed, and it is now incompatible with the drivers/rtc
> >> framework.
> >>
> >> Remove the chardev completely. If anyone wants to add the functionality
> >> later, that shoudl be done through rtc_register_device().
> >>
> >> The remaining portions of the driver basically implement a single
> >> procfs file that may or may not be used anywhere. Not sure why this
> >> is in drivers/input/ though.
> >>
> >> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> > Acked-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
>
> A year ago I did actually converted this driver to the RTC framework.
> But after some testing on my physical box (a 715/64 PA-RISC machine
> with HIL connector) I realized that the SDC in that machine doesn't
> provide a functional RTC, and even more important, on that box we don't
> need this RTC because the system provides a built-in RTC on-mainboard instead.
> So, I never pushed my changes upstream, which can still be found here:
> https://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux.git/commit/?h=hp_sdc_rtc_conversion&id=0d4250dbcfa2bb8b326ce7721e19e10a66f1eb92
>
> So, I don't think any PA-RISC machine needs this driver, and as such
> I'm happy to give my:
> Acked-by: Helge Deller <deller@xxxxxx>
>
> I even think the whole driver can go away...
>
> Helge
>
> PS: Maybe some really old 68000-based HP machines needed that, but
> I don't know if any recent Linux kernel runs on those old boxes any
> longer...
>
>
> >> ---
> >> drivers/input/misc/hp_sdc_rtc.c | 342 --------------------------------
> >> 1 file changed, 342 deletions(-)
> >>
> >> diff --git a/drivers/input/misc/hp_sdc_rtc.c b/drivers/input/misc/hp_sdc_rtc.c
> >> index abca895a6156..199bc17ddb1d 100644
> >> --- a/drivers/input/misc/hp_sdc_rtc.c
> >> +++ b/drivers/input/misc/hp_sdc_rtc.c
> >> @@ -53,28 +53,10 @@ MODULE_LICENSE("Dual BSD/GPL");
> >>
> >> #define RTC_VERSION "1.10d"
> >>
> >> -static DEFINE_MUTEX(hp_sdc_rtc_mutex);
> >> static unsigned long epoch = 2000;
> >>
> >> static struct semaphore i8042tregs;
> >>
> >> -static hp_sdc_irqhook hp_sdc_rtc_isr;
> >> -
> >> -static struct fasync_struct *hp_sdc_rtc_async_queue;
> >> -
> >> -static DECLARE_WAIT_QUEUE_HEAD(hp_sdc_rtc_wait);
> >> -
> >> -static ssize_t hp_sdc_rtc_read(struct file *file, char __user *buf,
> >> - size_t count, loff_t *ppos);
> >> -
> >> -static long hp_sdc_rtc_unlocked_ioctl(struct file *file,
> >> - unsigned int cmd, unsigned long arg);
> >> -
> >> -static unsigned int hp_sdc_rtc_poll(struct file *file, poll_table *wait);
> >> -
> >> -static int hp_sdc_rtc_open(struct inode *inode, struct file *file);
> >> -static int hp_sdc_rtc_fasync (int fd, struct file *filp, int on);
> >> -
> >> static void hp_sdc_rtc_isr (int irq, void *dev_id,
> >> uint8_t status, uint8_t data)
> >> {
> >> @@ -283,151 +265,6 @@ static inline int hp_sdc_rtc_read_ct(struct timespec64 *res) {
> >> return 0;
> >> }
> >>
> >> -
> >> -#if 0 /* not used yet */
> >> -/* Set the i8042 real-time clock */
> >> -static int hp_sdc_rtc_set_rt (struct timeval *setto)
> >> -{
> >> - uint32_t tenms;
> >> - unsigned int days;
> >> - hp_sdc_transaction t;
> >> - uint8_t tseq[11] = {
> >> - HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
> >> - HP_SDC_CMD_SET_RTMS, 3, 0, 0, 0,
> >> - HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
> >> - HP_SDC_CMD_SET_RTD, 2, 0, 0
> >> - };
> >> -
> >> - t.endidx = 10;
> >> -
> >> - if (0xffff < setto->tv_sec / 86400) return -1;
> >> - days = setto->tv_sec / 86400;
> >> - if (0xffff < setto->tv_usec / 1000000 / 86400) return -1;
> >> - days += ((setto->tv_sec % 86400) + setto->tv_usec / 1000000) / 86400;
> >> - if (days > 0xffff) return -1;
> >> -
> >> - if (0xffffff < setto->tv_sec) return -1;
> >> - tenms = setto->tv_sec * 100;
> >> - if (0xffffff < setto->tv_usec / 10000) return -1;
> >> - tenms += setto->tv_usec / 10000;
> >> - if (tenms > 0xffffff) return -1;
> >> -
> >> - tseq[3] = (uint8_t)(tenms & 0xff);
> >> - tseq[4] = (uint8_t)((tenms >> 8) & 0xff);
> >> - tseq[5] = (uint8_t)((tenms >> 16) & 0xff);
> >> -
> >> - tseq[9] = (uint8_t)(days & 0xff);
> >> - tseq[10] = (uint8_t)((days >> 8) & 0xff);
> >> -
> >> - t.seq = tseq;
> >> -
> >> - if (hp_sdc_enqueue_transaction(&t)) return -1;
> >> - return 0;
> >> -}
> >> -
> >> -/* Set the i8042 fast handshake timer */
> >> -static int hp_sdc_rtc_set_fhs (struct timeval *setto)
> >> -{
> >> - uint32_t tenms;
> >> - hp_sdc_transaction t;
> >> - uint8_t tseq[5] = {
> >> - HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
> >> - HP_SDC_CMD_SET_FHS, 2, 0, 0
> >> - };
> >> -
> >> - t.endidx = 4;
> >> -
> >> - if (0xffff < setto->tv_sec) return -1;
> >> - tenms = setto->tv_sec * 100;
> >> - if (0xffff < setto->tv_usec / 10000) return -1;
> >> - tenms += setto->tv_usec / 10000;
> >> - if (tenms > 0xffff) return -1;
> >> -
> >> - tseq[3] = (uint8_t)(tenms & 0xff);
> >> - tseq[4] = (uint8_t)((tenms >> 8) & 0xff);
> >> -
> >> - t.seq = tseq;
> >> -
> >> - if (hp_sdc_enqueue_transaction(&t)) return -1;
> >> - return 0;
> >> -}
> >> -
> >> -
> >> -/* Set the i8042 match timer (a.k.a. alarm) */
> >> -#define hp_sdc_rtc_set_mt (setto) \
> >> - hp_sdc_rtc_set_i8042timer(setto, HP_SDC_CMD_SET_MT)
> >> -
> >> -/* Set the i8042 delay timer */
> >> -#define hp_sdc_rtc_set_dt (setto) \
> >> - hp_sdc_rtc_set_i8042timer(setto, HP_SDC_CMD_SET_DT)
> >> -
> >> -/* Set the i8042 cycle timer (a.k.a. periodic) */
> >> -#define hp_sdc_rtc_set_ct (setto) \
> >> - hp_sdc_rtc_set_i8042timer(setto, HP_SDC_CMD_SET_CT)
> >> -
> >> -/* Set one of the i8042 3-byte wide timers */
> >> -static int hp_sdc_rtc_set_i8042timer (struct timeval *setto, uint8_t setcmd)
> >> -{
> >> - uint32_t tenms;
> >> - hp_sdc_transaction t;
> >> - uint8_t tseq[6] = {
> >> - HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT,
> >> - 0, 3, 0, 0, 0
> >> - };
> >> -
> >> - t.endidx = 6;
> >> -
> >> - if (0xffffff < setto->tv_sec) return -1;
> >> - tenms = setto->tv_sec * 100;
> >> - if (0xffffff < setto->tv_usec / 10000) return -1;
> >> - tenms += setto->tv_usec / 10000;
> >> - if (tenms > 0xffffff) return -1;
> >> -
> >> - tseq[1] = setcmd;
> >> - tseq[3] = (uint8_t)(tenms & 0xff);
> >> - tseq[4] = (uint8_t)((tenms >> 8) & 0xff);
> >> - tseq[5] = (uint8_t)((tenms >> 16) & 0xff);
> >> -
> >> - t.seq = tseq;
> >> -
> >> - if (hp_sdc_enqueue_transaction(&t)) {
> >> - return -1;
> >> - }
> >> - return 0;
> >> -}
> >> -#endif
> >> -
> >> -static ssize_t hp_sdc_rtc_read(struct file *file, char __user *buf,
> >> - size_t count, loff_t *ppos) {
> >> - ssize_t retval;
> >> -
> >> - if (count < sizeof(unsigned long))
> >> - return -EINVAL;
> >> -
> >> - retval = put_user(68, (unsigned long __user *)buf);
> >> - return retval;
> >> -}
> >> -
> >> -static __poll_t hp_sdc_rtc_poll(struct file *file, poll_table *wait)
> >> -{
> >> - unsigned long l;
> >> -
> >> - l = 0;
> >> - if (l != 0)
> >> - return EPOLLIN | EPOLLRDNORM;
> >> - return 0;
> >> -}
> >> -
> >> -static int hp_sdc_rtc_open(struct inode *inode, struct file *file)
> >> -{
> >> - return 0;
> >> -}
> >> -
> >> -static int hp_sdc_rtc_fasync (int fd, struct file *filp, int on)
> >> -{
> >> - return fasync_helper (fd, filp, on, &hp_sdc_rtc_async_queue);
> >> -}
> >> -
> >> static int hp_sdc_rtc_proc_show(struct seq_file *m, void *v)
> >> {
> >> #define YN(bit) ("no")
> >> @@ -507,182 +344,6 @@ static int hp_sdc_rtc_proc_show(struct seq_file *m, void *v)
> >> #undef NY
> >> }
> >>
> >> -static int hp_sdc_rtc_ioctl(struct file *file,
> >> - unsigned int cmd, unsigned long arg)
> >> -{
> >> -#if 1
> >> - return -EINVAL;
> >> -#else
> >> -
> >> - struct rtc_time wtime;
> >> - struct timeval ttime;
> >> - int use_wtime = 0;
> >> -
> >> - /* This needs major work. */
> >> -
> >> - switch (cmd) {
> >> -
> >> - case RTC_AIE_OFF: /* Mask alarm int. enab. bit */
> >> - case RTC_AIE_ON: /* Allow alarm interrupts. */
> >> - case RTC_PIE_OFF: /* Mask periodic int. enab. bit */
> >> - case RTC_PIE_ON: /* Allow periodic ints */
> >> - case RTC_UIE_ON: /* Allow ints for RTC updates. */
> >> - case RTC_UIE_OFF: /* Allow ints for RTC updates. */
> >> - {
> >> - /* We cannot mask individual user timers and we
> >> - cannot tell them apart when they occur, so it
> >> - would be disingenuous to succeed these IOCTLs */
> >> - return -EINVAL;
> >> - }
> >> - case RTC_ALM_READ: /* Read the present alarm time */
> >> - {
> >> - if (hp_sdc_rtc_read_mt(&ttime)) return -EFAULT;
> >> - if (hp_sdc_rtc_read_bbrtc(&wtime)) return -EFAULT;
> >> -
> >> - wtime.tm_hour = ttime.tv_sec / 3600; ttime.tv_sec %= 3600;
> >> - wtime.tm_min = ttime.tv_sec / 60; ttime.tv_sec %= 60;
> >> - wtime.tm_sec = ttime.tv_sec;
> >> -
> >> - break;
> >> - }
> >> - case RTC_IRQP_READ: /* Read the periodic IRQ rate. */
> >> - {
> >> - return put_user(hp_sdc_rtc_freq, (unsigned long *)arg);
> >> - }
> >> - case RTC_IRQP_SET: /* Set periodic IRQ rate. */
> >> - {
> >> - /*
> >> - * The max we can do is 100Hz.
> >> - */
> >> -
> >> - if ((arg < 1) || (arg > 100)) return -EINVAL;
> >> - ttime.tv_sec = 0;
> >> - ttime.tv_usec = 1000000 / arg;
> >> - if (hp_sdc_rtc_set_ct(&ttime)) return -EFAULT;
> >> - hp_sdc_rtc_freq = arg;
> >> - return 0;
> >> - }
> >> - case RTC_ALM_SET: /* Store a time into the alarm */
> >> - {
> >> - /*
> >> - * This expects a struct hp_sdc_rtc_time. Writing 0xff means
> >> - * "don't care" or "match all" for PC timers. The HP SDC
> >> - * does not support that perk, but it could be emulated fairly
> >> - * easily. Only the tm_hour, tm_min and tm_sec are used.
> >> - * We could do it with 10ms accuracy with the HP SDC, if the
> >> - * rtc interface left us a way to do that.
> >> - */
> >> - struct hp_sdc_rtc_time alm_tm;
> >> -
> >> - if (copy_from_user(&alm_tm, (struct hp_sdc_rtc_time*)arg,
> >> - sizeof(struct hp_sdc_rtc_time)))
> >> - return -EFAULT;
> >> -
> >> - if (alm_tm.tm_hour > 23) return -EINVAL;
> >> - if (alm_tm.tm_min > 59) return -EINVAL;
> >> - if (alm_tm.tm_sec > 59) return -EINVAL;
> >> -
> >> - ttime.sec = alm_tm.tm_hour * 3600 +
> >> - alm_tm.tm_min * 60 + alm_tm.tm_sec;
> >> - ttime.usec = 0;
> >> - if (hp_sdc_rtc_set_mt(&ttime)) return -EFAULT;
> >> - return 0;
> >> - }
> >> - case RTC_RD_TIME: /* Read the time/date from RTC */
> >> - {
> >> - if (hp_sdc_rtc_read_bbrtc(&wtime)) return -EFAULT;
> >> - break;
> >> - }
> >> - case RTC_SET_TIME: /* Set the RTC */
> >> - {
> >> - struct rtc_time hp_sdc_rtc_tm;
> >> - unsigned char mon, day, hrs, min, sec, leap_yr;
> >> - unsigned int yrs;
> >> -
> >> - if (!capable(CAP_SYS_TIME))
> >> - return -EACCES;
> >> - if (copy_from_user(&hp_sdc_rtc_tm, (struct rtc_time *)arg,
> >> - sizeof(struct rtc_time)))
> >> - return -EFAULT;
> >> -
> >> - yrs = hp_sdc_rtc_tm.tm_year + 1900;
> >> - mon = hp_sdc_rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
> >> - day = hp_sdc_rtc_tm.tm_mday;
> >> - hrs = hp_sdc_rtc_tm.tm_hour;
> >> - min = hp_sdc_rtc_tm.tm_min;
> >> - sec = hp_sdc_rtc_tm.tm_sec;
> >> -
> >> - if (yrs < 1970)
> >> - return -EINVAL;
> >> -
> >> - leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
> >> -
> >> - if ((mon > 12) || (day == 0))
> >> - return -EINVAL;
> >> - if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
> >> - return -EINVAL;
> >> - if ((hrs >= 24) || (min >= 60) || (sec >= 60))
> >> - return -EINVAL;
> >> -
> >> - if ((yrs -= eH) > 255) /* They are unsigned */
> >> - return -EINVAL;
> >> -
> >> -
> >> - return 0;
> >> - }
> >> - case RTC_EPOCH_READ: /* Read the epoch. */
> >> - {
> >> - return put_user (epoch, (unsigned long *)arg);
> >> - }
> >> - case RTC_EPOCH_SET: /* Set the epoch. */
> >> - {
> >> - /*
> >> - * There were no RTC clocks before 1900.
> >> - */
> >> - if (arg < 1900)
> >> - return -EINVAL;
> >> - if (!capable(CAP_SYS_TIME))
> >> - return -EACCES;
> >> -
> >> - epoch = arg;
> >> - return 0;
> >> - }
> >> - default:
> >> - return -EINVAL;
> >> - }
> >> - return copy_to_user((void *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
> >> -#endif
> >> -}
> >> -
> >> -static long hp_sdc_rtc_unlocked_ioctl(struct file *file,
> >> - unsigned int cmd, unsigned long arg)
> >> -{
> >> - int ret;
> >> -
> >> - mutex_lock(&hp_sdc_rtc_mutex);
> >> - ret = hp_sdc_rtc_ioctl(file, cmd, arg);
> >> - mutex_unlock(&hp_sdc_rtc_mutex);
> >> -
> >> - return ret;
> >> -}
> >> -
> >> -
> >> -static const struct file_operations hp_sdc_rtc_fops = {
> >> - .owner = THIS_MODULE,
> >> - .llseek = no_llseek,
> >> - .read = hp_sdc_rtc_read,
> >> - .poll = hp_sdc_rtc_poll,
> >> - .unlocked_ioctl = hp_sdc_rtc_unlocked_ioctl,
> >> - .open = hp_sdc_rtc_open,
> >> - .fasync = hp_sdc_rtc_fasync,
> >> -};
> >> -
> >> -static struct miscdevice hp_sdc_rtc_dev = {
> >> - .minor = RTC_MINOR,
> >> - .name = "rtc_HIL",
> >> - .fops = &hp_sdc_rtc_fops
> >> -};
> >> -
> >> static int __init hp_sdc_rtc_init(void)
> >> {
> >> int ret;
> >> @@ -696,8 +357,6 @@ static int __init hp_sdc_rtc_init(void)
> >>
> >> if ((ret = hp_sdc_request_timer_irq(&hp_sdc_rtc_isr)))
> >> return ret;
> >> - if (misc_register(&hp_sdc_rtc_dev) != 0)
> >> - printk(KERN_INFO "Could not register misc. dev for i8042 rtc\n");
> >>
> >> proc_create_single("driver/rtc", 0, NULL, hp_sdc_rtc_proc_show);
> >>
> >> @@ -710,7 +369,6 @@ static int __init hp_sdc_rtc_init(void)
> >> static void __exit hp_sdc_rtc_exit(void)
> >> {
> >> remove_proc_entry ("driver/rtc", NULL);
> >> - misc_deregister(&hp_sdc_rtc_dev);
> >> hp_sdc_release_timer_irq(hp_sdc_rtc_isr);
> >> printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support unloaded\n");
> >> }
> >> --
> >> 2.20.0