[PATCH net-next v7 4/5] ptp: clockmatrix: Fix caps.max_adj to reflect DPLL_MAX_FREQ_OFFSET[MAX_FFO]

[Min Li]

From: Min Li <min.li.xe@xxxxxxxxxxx>

Query MAX_FREQ_OFFSET register to set the proper limit.

Signed-off-by: Min Li <min.li.xe@xxxxxxxxxxx>
---
 drivers/ptp/ptp_clockmatrix.c    | 43 +++++++++++++++++++++++++-------
 drivers/ptp/ptp_clockmatrix.h    |  1 +
 include/linux/mfd/idt8a340_reg.h |  1 +
 3 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/drivers/ptp/ptp_clockmatrix.c b/drivers/ptp/ptp_clockmatrix.c
index 21f3a2c179f5..cd7b3110f8e4 100644
--- a/drivers/ptp/ptp_clockmatrix.c
+++ b/drivers/ptp/ptp_clockmatrix.c
@@ -1038,7 +1038,7 @@ static int _idtcm_adjtime_deprecated(struct idtcm_channel *channel, s64 delta)
 	s64 now;
 
 	if (abs(delta) < PHASE_PULL_IN_THRESHOLD_NS_DEPRECATED) {
-		err = channel->do_phase_pull_in(channel, delta, 0);
+		err = channel->do_phase_pull_in(channel, delta, channel->caps.max_adj);
 	} else {
 		idtcm->calculate_overhead_flag = 1;
 
@@ -1594,7 +1594,7 @@ static int do_phase_pull_in_sw(struct idtcm_channel *channel,
 	if (abs(delta_ns) < PHASE_PULL_IN_MIN_THRESHOLD_NS)
 		return 0;
 
-	if (max_ffo_ppb == 0)
+	if (max_ffo_ppb == 0 || max_ffo_ppb > PHASE_PULL_IN_MAX_PPB)
 		max_ffo_ppb = PHASE_PULL_IN_MAX_PPB;
 
 	/* For most cases, keep phase pull-in duration 1 second */
@@ -1880,7 +1880,7 @@ static int idtcm_adjtime(struct ptp_clock_info *ptp, s64 delta)
 	mutex_lock(idtcm->lock);
 
 	if (abs(delta) < PHASE_PULL_IN_THRESHOLD_NS) {
-		err = channel->do_phase_pull_in(channel, delta, 0);
+		err = channel->do_phase_pull_in(channel, delta, channel->caps.max_adj);
 	} else {
 		if (delta >= 0) {
 			ts = ns_to_timespec64(delta);
@@ -1927,9 +1927,6 @@ static int idtcm_adjfine(struct ptp_clock_info *ptp,  long scaled_ppm)
 	if (channel->phase_pull_in == true)
 		return 0;
 
-	if (scaled_ppm == channel->current_freq_scaled_ppm)
-		return 0;
-
 	mutex_lock(idtcm->lock);
 	err = _idtcm_adjfine(channel, scaled_ppm);
 	mutex_unlock(idtcm->lock);
@@ -2054,7 +2051,7 @@ static struct ptp_pin_desc pin_config[MAX_TOD][MAX_REF_CLK];
 
 static const struct ptp_clock_info idtcm_caps = {
 	.owner		= THIS_MODULE,
-	.max_adj	= 244000,
+	.max_adj	= MAX_FFO_PPB,
 	.n_per_out	= 12,
 	.n_ext_ts	= MAX_TOD,
 	.n_pins		= MAX_REF_CLK,
@@ -2071,7 +2068,7 @@ static const struct ptp_clock_info idtcm_caps = {
 
 static const struct ptp_clock_info idtcm_caps_deprecated = {
 	.owner		= THIS_MODULE,
-	.max_adj	= 244000,
+	.max_adj	= MAX_FFO_PPB,
 	.n_per_out	= 12,
 	.n_ext_ts	= MAX_TOD,
 	.n_pins		= MAX_REF_CLK,
@@ -2242,6 +2239,25 @@ static int configure_channel_tod(struct idtcm_channel *channel, u32 index)
 	return 0;
 }
 
+static int initialize_max_adj(struct idtcm_channel *channel)
+{
+	struct idtcm *idtcm = channel->idtcm;
+	u8 ffo_ppm;
+	int err;
+
+	err = idtcm_read(idtcm, channel->dpll_n, DPLL_MAX_FREQ_OFFSET,
+			 &ffo_ppm, sizeof(ffo_ppm));
+	if (err)
+		return err;
+
+	if (ffo_ppm && ffo_ppm <= (MAX_FFO_PPB / 1000))
+		channel->caps.max_adj = ffo_ppm * 1000;
+	else
+		channel->caps.max_adj = MAX_FFO_PPB;
+
+	return 0;
+}
+
 static int idtcm_enable_channel(struct idtcm *idtcm, u32 index)
 {
 	struct idtcm_channel *channel;
@@ -2285,6 +2301,10 @@ static int idtcm_enable_channel(struct idtcm *idtcm, u32 index)
 		ppd->chan = index;
 	}
 
+	err = initialize_max_adj(channel);
+	if (err)
+		return err;
+
 	err = initialize_dco_operating_mode(channel);
 	if (err)
 		return err;
@@ -2437,8 +2457,13 @@ static int idtcm_probe(struct platform_device *pdev)
 
 	err = idtcm_load_firmware(idtcm, &pdev->dev);
 
-	if (err)
+	if (err) {
+		if (err == -ENOENT) {
+			mutex_unlock(idtcm->lock);
+			return -EPROBE_DEFER;
+		}
 		dev_warn(idtcm->dev, "loading firmware failed with %d", err);
+	}
 
 	wait_for_chip_ready(idtcm);
 
diff --git a/drivers/ptp/ptp_clockmatrix.h b/drivers/ptp/ptp_clockmatrix.h
index ad39dc6decdf..31d90b1bf025 100644
--- a/drivers/ptp/ptp_clockmatrix.h
+++ b/drivers/ptp/ptp_clockmatrix.h
@@ -19,6 +19,7 @@
 #define MAX_REF_CLK	(16)
 
 #define MAX_ABS_WRITE_PHASE_NANOSECONDS (107374182L)
+#define MAX_FFO_PPB (244000)
 
 #define TOD_MASK_ADDR		(0xFFA5)
 #define DEFAULT_TOD_MASK	(0x04)
diff --git a/include/linux/mfd/idt8a340_reg.h b/include/linux/mfd/idt8a340_reg.h
index b680a0eb5f68..13b36f4858b3 100644
--- a/include/linux/mfd/idt8a340_reg.h
+++ b/include/linux/mfd/idt8a340_reg.h
@@ -192,6 +192,7 @@
 #define DPLL_CTRL_REG_0                   0x0002
 #define DPLL_CTRL_REG_1                   0x0003
 #define DPLL_CTRL_REG_2                   0x0004
+#define DPLL_MAX_FREQ_OFFSET              0x0025
 #define DPLL_WF_TIMER                     0x002c
 #define DPLL_WP_TIMER                     0x002e
 #define DPLL_TOD_SYNC_CFG                 0x0031
-- 
2.39.2