fsi: master: Add boolean parameter to link_enable function

Add the ability to disable a link with a boolean parameter to the
link_enable function. This is necessary so that the master can disable
links that it isn't using; for example, links to slaves that fail
initialization.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>

drivers/fsi/fsi-core.c

@@ -1157,7 +1157,7 @@ static int fsi_master_write(struct fsi_master *master, int link,
 static int fsi_master_link_enable(struct fsi_master *master, int link)
 {
 	if (master->link_enable)
-		return master->link_enable(master, link);
+		return master->link_enable(master, link, true);
 
 	return 0;
 }

drivers/fsi/fsi-master-aspeed.c

@@ -301,7 +301,8 @@ static int aspeed_master_write(struct fsi_master *master, int link,
 	return 0;
 }
 
-static int aspeed_master_link_enable(struct fsi_master *master, int link)
+static int aspeed_master_link_enable(struct fsi_master *master, int link,
+				     bool enable)
 {
 	struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
 	int idx, bit, ret;
@@ -312,6 +313,10 @@ static int aspeed_master_link_enable(struct fsi_master *master, int link)
 
 	reg = cpu_to_be32(0x80000000 >> bit);
 
+	if (!enable)
+		return opb_writel(aspeed, ctrl_base + FSI_MCENP0 + (4 * idx),
+				  reg);
+
 	ret = opb_writel(aspeed, ctrl_base + FSI_MSENP0 + (4 * idx), reg);
 	if (ret)
 		return ret;

drivers/fsi/fsi-master-ast-cf.c

@@ -1039,7 +1039,8 @@ static void fsi_master_acf_setup_external(struct fsi_master_acf *master)
 	gpiod_direction_input(master->gpio_data);
 }
 
-static int fsi_master_acf_link_enable(struct fsi_master *_master, int link)
+static int fsi_master_acf_link_enable(struct fsi_master *_master, int link,
+				      bool enable)
 {
 	struct fsi_master_acf *master = to_fsi_master_acf(_master);
 	int rc = -EBUSY;
@@ -1049,7 +1050,7 @@ static int fsi_master_acf_link_enable(struct fsi_master *_master, int link)
 
 	mutex_lock(&master->lock);
 	if (!master->external_mode) {
-		gpiod_set_value(master->gpio_enable, 1);
+		gpiod_set_value(master->gpio_enable, enable ? 1 : 0);
 		rc = 0;
 	}
 	mutex_unlock(&master->lock);

drivers/fsi/fsi-master-gpio.c

@@ -678,7 +678,8 @@ static void fsi_master_gpio_init_external(struct fsi_master_gpio *master)
 	gpiod_direction_input(master->gpio_data);
 }
 
-static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link)
+static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link,
+				       bool enable)
 {
 	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
 	int rc = -EBUSY;
@@ -688,7 +689,7 @@ static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link)
 
 	mutex_lock(&master->cmd_lock);
 	if (!master->external_mode) {
-		gpiod_set_value(master->gpio_enable, 1);
+		gpiod_set_value(master->gpio_enable, enable ? 1 : 0);
 		rc = 0;
 	}
 	mutex_unlock(&master->cmd_lock);

drivers/fsi/fsi-master-hub.c

@@ -77,7 +77,8 @@ static int hub_master_break(struct fsi_master *master, int link)
 	return hub_master_write(master, link, 0, addr, &cmd, sizeof(cmd));
 }
 
-static int hub_master_link_enable(struct fsi_master *master, int link)
+static int hub_master_link_enable(struct fsi_master *master, int link,
+				  bool enable)
 {
 	struct fsi_master_hub *hub = to_fsi_master_hub(master);
 	int idx, bit;
@@ -89,6 +90,10 @@ static int hub_master_link_enable(struct fsi_master *master, int link)
 
 	reg = cpu_to_be32(0x80000000 >> bit);
 
+	if (!enable)
+		return fsi_device_write(hub->upstream, FSI_MCENP0 + (4 * idx),
+					&reg, 4);
+
 	rc = fsi_device_write(hub->upstream, FSI_MSENP0 + (4 * idx), &reg, 4);
 
 	mdelay(FSI_LINK_ENABLE_SETUP_TIME);

drivers/fsi/fsi-master.h

@@ -130,7 +130,8 @@ struct fsi_master {
 				uint32_t addr, const void *val, size_t size);
 	int		(*term)(struct fsi_master *, int link, uint8_t id);
 	int		(*send_break)(struct fsi_master *, int link);
-	int		(*link_enable)(struct fsi_master *, int link);
+	int		(*link_enable)(struct fsi_master *, int link,
+				       bool enable);
 	int		(*link_config)(struct fsi_master *, int link,
 				       u8 t_send_delay, u8 t_echo_delay);
 };