net: ethernet: ti: cpts: rework initialization/deinitialization

The current implementation CPTS initialization and deinitialization
(represented by cpts_register/unregister()) does too many static
initialization from .ndo_open(), which is reasonable to do once at probe
time instead, and also require caller to allocate memory for struct cpts,
which is internal for CPTS driver in general.

This patch splits CPTS initialization and deinitialization on two parts:

- static initializtion cpts_create()/cpts_release() which expected to be
executed when parent driver is probed/removed;

- dynamic part cpts_register/unregister() which expected to be executed
when network device is opened/closed.

As result, current code of CPTS parent driver - CPSW - will be simplified
(and it also will allow simplify adding support for Keystone 2 devices in
the future), plus more initialization errors will be catched earlier. In
addition, this change allows to clean up cpts.h for the case when CPTS is
disabled.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 58 insertions, 41 deletions

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index fe1bb7f02f2e..31cd83fa10ce 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -248,24 +248,6 @@ static void cpts_overflow_check(struct work_struct *work)
 	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
 }
 
-static void cpts_clk_init(struct device *dev, struct cpts *cpts)
-{
-	if (!cpts->refclk) {
-		cpts->refclk = devm_clk_get(dev, "cpts");
-		if (IS_ERR(cpts->refclk)) {
-			dev_err(dev, "Failed to get cpts refclk\n");
-			cpts->refclk = NULL;
-			return;
-		}
-	}
-	clk_prepare_enable(cpts->refclk);
-}
-
-static void cpts_clk_release(struct cpts *cpts)
-{
-	clk_disable_unprepare(cpts->refclk);
-}
-
 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
 		      u16 ts_seqid, u8 ts_msgtype)
 {
@@ -372,34 +354,23 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 }
 EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
 
-int cpts_register(struct device *dev, struct cpts *cpts,
-		  u32 mult, u32 shift)
+int cpts_register(struct cpts *cpts)
 {
 	int err, i;
 
-	cpts->info = cpts_info;
-	spin_lock_init(&cpts->lock);
-
-	cpts->cc.read = cpts_systim_read;
-	cpts->cc.mask = CLOCKSOURCE_MASK(32);
-	cpts->cc_mult = mult;
-	cpts->cc.mult = mult;
-	cpts->cc.shift = shift;
-
 	INIT_LIST_HEAD(&cpts->events);
 	INIT_LIST_HEAD(&cpts->pool);
 	for (i = 0; i < CPTS_MAX_EVENTS; i++)
 		list_add(&cpts->pool_data[i].list, &cpts->pool);
 
-	cpts_clk_init(dev, cpts);
+	clk_enable(cpts->refclk);
+
 	cpts_write32(cpts, CPTS_EN, control);
 	cpts_write32(cpts, TS_PEND_EN, int_enable);
 
 	timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
 
-	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
-
-	cpts->clock = ptp_clock_register(&cpts->info, dev);
+	cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
 	if (IS_ERR(cpts->clock)) {
 		err = PTR_ERR(cpts->clock);
 		cpts->clock = NULL;
@@ -412,27 +383,73 @@ int cpts_register(struct device *dev, struct cpts *cpts,
 	return 0;
 
 err_ptp:
-	if (cpts->refclk)
-		cpts_clk_release(cpts);
+	clk_disable(cpts->refclk);
 	return err;
 }
 EXPORT_SYMBOL_GPL(cpts_register);
 
 void cpts_unregister(struct cpts *cpts)
 {
-	if (cpts->clock) {
-		ptp_clock_unregister(cpts->clock);
-		cancel_delayed_work_sync(&cpts->overflow_work);
-	}
+	if (WARN_ON(!cpts->clock))
+		return;
+
+	cancel_delayed_work_sync(&cpts->overflow_work);
+
+	ptp_clock_unregister(cpts->clock);
+	cpts->clock = NULL;
 
 	cpts_write32(cpts, 0, int_enable);
 	cpts_write32(cpts, 0, control);
 
-	if (cpts->refclk)
-		cpts_clk_release(cpts);
+	clk_disable(cpts->refclk);
 }
 EXPORT_SYMBOL_GPL(cpts_unregister);
 
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 u32 mult, u32 shift)
+{
+	struct cpts *cpts;
+
+	cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
+	if (!cpts)
+		return ERR_PTR(-ENOMEM);
+
+	cpts->dev = dev;
+	cpts->reg = (struct cpsw_cpts __iomem *)regs;
+	spin_lock_init(&cpts->lock);
+	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
+
+	cpts->refclk = devm_clk_get(dev, "cpts");
+	if (IS_ERR(cpts->refclk)) {
+		dev_err(dev, "Failed to get cpts refclk\n");
+		return ERR_PTR(PTR_ERR(cpts->refclk));
+	}
+
+	clk_prepare(cpts->refclk);
+
+	cpts->cc.read = cpts_systim_read;
+	cpts->cc.mask = CLOCKSOURCE_MASK(32);
+	cpts->cc.shift = shift;
+	cpts->cc_mult = mult;
+	cpts->cc.mult = mult;
+	cpts->info = cpts_info;
+
+	return cpts;
+}
+EXPORT_SYMBOL_GPL(cpts_create);
+
+void cpts_release(struct cpts *cpts)
+{
+	if (!cpts)
+		return;
+
+	if (WARN_ON(!cpts->refclk))
+		return;
+
+	clk_unprepare(cpts->refclk);
+}
+EXPORT_SYMBOL_GPL(cpts_release);
+
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("TI CPTS driver");
 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");