ptp: introduce programmable pins.
This patch adds a pair of new ioctls to the PTP Hardware Clock device
interface. Using the ioctls, user space programs can query each pin to
find out its current function and also reprogram a different function
if desired.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 34a0c60..419056d 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -25,6 +25,96 @@
#include "ptp_private.h"
+static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
+ enum ptp_pin_function func, unsigned int chan)
+{
+ struct ptp_clock_request rq;
+ int err = 0;
+
+ memset(&rq, 0, sizeof(rq));
+
+ switch (func) {
+ case PTP_PF_NONE:
+ break;
+ case PTP_PF_EXTTS:
+ rq.type = PTP_CLK_REQ_EXTTS;
+ rq.extts.index = chan;
+ err = ops->enable(ops, &rq, 0);
+ break;
+ case PTP_PF_PEROUT:
+ rq.type = PTP_CLK_REQ_PEROUT;
+ rq.perout.index = chan;
+ err = ops->enable(ops, &rq, 0);
+ break;
+ case PTP_PF_PHYSYNC:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return err;
+}
+
+int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
+ enum ptp_pin_function func, unsigned int chan)
+{
+ struct ptp_clock_info *info = ptp->info;
+ struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin];
+ unsigned int i;
+
+ /* Check to see if any other pin previously had this function. */
+ for (i = 0; i < info->n_pins; i++) {
+ if (info->pin_config[i].func == func &&
+ info->pin_config[i].chan == chan) {
+ pin1 = &info->pin_config[i];
+ break;
+ }
+ }
+ if (pin1 && i == pin)
+ return 0;
+
+ /* Check the desired function and channel. */
+ switch (func) {
+ case PTP_PF_NONE:
+ break;
+ case PTP_PF_EXTTS:
+ if (chan >= info->n_ext_ts)
+ return -EINVAL;
+ break;
+ case PTP_PF_PEROUT:
+ if (chan >= info->n_per_out)
+ return -EINVAL;
+ break;
+ case PTP_PF_PHYSYNC:
+ pr_err("sorry, cannot reassign the calibration pin\n");
+ return -EINVAL;
+ default:
+ return -EINVAL;
+ }
+
+ if (pin2->func == PTP_PF_PHYSYNC) {
+ pr_err("sorry, cannot reprogram the calibration pin\n");
+ return -EINVAL;
+ }
+
+ if (info->verify(info, pin, func, chan)) {
+ pr_err("driver cannot use function %u on pin %u\n", func, chan);
+ return -EOPNOTSUPP;
+ }
+
+ /* Disable whatever function was previously assigned. */
+ if (pin1) {
+ ptp_disable_pinfunc(info, func, chan);
+ pin1->func = PTP_PF_NONE;
+ pin1->chan = 0;
+ }
+ ptp_disable_pinfunc(info, pin2->func, pin2->chan);
+ pin2->func = func;
+ pin2->chan = chan;
+
+ return 0;
+}
+
int ptp_open(struct posix_clock *pc, fmode_t fmode)
{
return 0;
@@ -35,12 +125,13 @@
struct ptp_clock_caps caps;
struct ptp_clock_request req;
struct ptp_sys_offset *sysoff = NULL;
+ struct ptp_pin_desc pd;
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
struct ptp_clock_info *ops = ptp->info;
struct ptp_clock_time *pct;
struct timespec ts;
int enable, err = 0;
- unsigned int i;
+ unsigned int i, pin_index;
switch (cmd) {
@@ -51,6 +142,7 @@
caps.n_ext_ts = ptp->info->n_ext_ts;
caps.n_per_out = ptp->info->n_per_out;
caps.pps = ptp->info->pps;
+ caps.n_pins = ptp->info->n_pins;
if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
err = -EFAULT;
break;
@@ -126,6 +218,40 @@
err = -EFAULT;
break;
+ case PTP_PIN_GETFUNC:
+ if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
+ err = -EFAULT;
+ break;
+ }
+ pin_index = pd.index;
+ if (pin_index >= ops->n_pins) {
+ err = -EINVAL;
+ break;
+ }
+ if (mutex_lock_interruptible(&ptp->pincfg_mux))
+ return -ERESTARTSYS;
+ pd = ops->pin_config[pin_index];
+ mutex_unlock(&ptp->pincfg_mux);
+ if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
+ err = -EFAULT;
+ break;
+
+ case PTP_PIN_SETFUNC:
+ if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
+ err = -EFAULT;
+ break;
+ }
+ pin_index = pd.index;
+ if (pin_index >= ops->n_pins) {
+ err = -EINVAL;
+ break;
+ }
+ if (mutex_lock_interruptible(&ptp->pincfg_mux))
+ return -ERESTARTSYS;
+ err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
+ mutex_unlock(&ptp->pincfg_mux);
+ break;
+
default:
err = -ENOTTY;
break;
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index a8319b2..e25d2bc 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -169,6 +169,7 @@
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
mutex_destroy(&ptp->tsevq_mux);
+ mutex_destroy(&ptp->pincfg_mux);
ida_simple_remove(&ptp_clocks_map, ptp->index);
kfree(ptp);
}
@@ -203,6 +204,7 @@
ptp->index = index;
spin_lock_init(&ptp->tsevq.lock);
mutex_init(&ptp->tsevq_mux);
+ mutex_init(&ptp->pincfg_mux);
init_waitqueue_head(&ptp->tsev_wq);
/* Create a new device in our class. */
@@ -249,6 +251,7 @@
device_destroy(ptp_class, ptp->devid);
no_device:
mutex_destroy(&ptp->tsevq_mux);
+ mutex_destroy(&ptp->pincfg_mux);
no_slot:
kfree(ptp);
no_memory:
@@ -305,6 +308,26 @@
}
EXPORT_SYMBOL(ptp_clock_index);
+int ptp_find_pin(struct ptp_clock *ptp,
+ enum ptp_pin_function func, unsigned int chan)
+{
+ struct ptp_pin_desc *pin = NULL;
+ int i;
+
+ mutex_lock(&ptp->pincfg_mux);
+ for (i = 0; i < ptp->info->n_pins; i++) {
+ if (ptp->info->pin_config[i].func == func &&
+ ptp->info->pin_config[i].chan == chan) {
+ pin = &ptp->info->pin_config[i];
+ break;
+ }
+ }
+ mutex_unlock(&ptp->pincfg_mux);
+
+ return pin ? i : -1;
+}
+EXPORT_SYMBOL(ptp_find_pin);
+
/* module operations */
static void __exit ptp_exit(void)
diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h
index df03f2e..b114a84 100644
--- a/drivers/ptp/ptp_private.h
+++ b/drivers/ptp/ptp_private.h
@@ -48,6 +48,7 @@
long dialed_frequency; /* remembers the frequency adjustment */
struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
struct mutex tsevq_mux; /* one process at a time reading the fifo */
+ struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
wait_queue_head_t tsev_wq;
int defunct; /* tells readers to go away when clock is being removed */
};
@@ -69,6 +70,10 @@
* see ptp_chardev.c
*/
+/* caller must hold pincfg_mux */
+int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
+ enum ptp_pin_function func, unsigned int chan);
+
long ptp_ioctl(struct posix_clock *pc,
unsigned int cmd, unsigned long arg);