ahci: Cache host controller version

This allows sysfs nodes to read the cached value directly instead of
powering up possibly runtime suspended controller.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 513b3fa74d78..8cdf0afd551d 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -251,9 +251,8 @@ static ssize_t ahci_show_host_version(struct device *dev,
 	struct Scsi_Host *shost = class_to_shost(dev);
 	struct ata_port *ap = ata_shost_to_port(shost);
 	struct ahci_host_priv *hpriv = ap->host->private_data;
-	void __iomem *mmio = hpriv->mmio;
 
-	return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
+	return sprintf(buf, "%x\n", hpriv->version);
 }
 
 static ssize_t ahci_show_port_cmd(struct device *dev,
@@ -509,6 +508,7 @@ void ahci_save_initial_config(struct device *dev, struct ahci_host_priv *hpriv)
 	/* record values to use during operation */
 	hpriv->cap = cap;
 	hpriv->cap2 = cap2;
+	hpriv->version = readl(mmio + HOST_VERSION);
 	hpriv->port_map = port_map;
 
 	if (!hpriv->start_engine)
@@ -2357,11 +2357,10 @@ static void ahci_port_stop(struct ata_port *ap)
 void ahci_print_info(struct ata_host *host, const char *scc_s)
 {
 	struct ahci_host_priv *hpriv = host->private_data;
-	void __iomem *mmio = hpriv->mmio;
 	u32 vers, cap, cap2, impl, speed;
 	const char *speed_s;
 
-	vers = readl(mmio + HOST_VERSION);
+	vers = hpriv->version;
 	cap = hpriv->cap;
 	cap2 = hpriv->cap2;
 	impl = hpriv->port_map;