[PATCH v11 05/20] platform/x86/intel/pmt: Do not remap when using callbacks

["Michael J. Ruhl" <michael.j.ruhl@intel.com>]

A callback indicates that the parent driver is responsible for accessing
the data area.  Creating a PMT memory remap is redundant.

If a read_telem callback has been provided, do not create a remap.

Enforce API usage where necessary.

Clean up open coded resource usage.

Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
---
 drivers/platform/x86/intel/pmt/class.c     | 21 +++++++++++++--------
 drivers/platform/x86/intel/pmt/class.h     |  2 +-
 drivers/platform/x86/intel/pmt/telemetry.c |  3 +++
 3 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/x86/intel/pmt/class.c b/drivers/platform/x86/intel/pmt/class.c
index 402d51df834a..1c7a372b4fc4 100644
--- a/drivers/platform/x86/intel/pmt/class.c
+++ b/drivers/platform/x86/intel/pmt/class.c
@@ -12,6 +12,7 @@
 #include <linux/log2.h>
 #include <linux/intel_vsec.h>
 #include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/ioport.h>
 #include <linux/minmax.h>
 #include <linux/module.h>
 #include <linux/mm.h>
@@ -373,7 +374,6 @@ static int intel_pmt_dev_register(struct intel_pmt_entry *entry,
 				  struct device *parent)
 {
 	struct intel_vsec_device *ivdev = dev_to_ivdev(parent);
-	struct resource res = {0};
 	struct device *dev;
 	int ret;
 
@@ -403,14 +403,19 @@ static int intel_pmt_dev_register(struct intel_pmt_entry *entry,
 	if (!entry->size)
 		return 0;
 
-	res.start = entry->base_addr;
-	res.end = res.start + entry->size - 1;
-	res.flags = IORESOURCE_MEM;
+	/*
+	 * The read_telem callback is responsible for this mapping, and may have
+	 * different requirements for use. If the callback is present do not
+	 * create the map.
+	 */
+	if (!(entry->cb && entry->cb->read_telem)) {
+		struct resource res = DEFINE_RES_MEM(entry->base_addr, entry->size);
 
-	entry->base = devm_ioremap_resource(dev, &res);
-	if (IS_ERR(entry->base)) {
-		ret = PTR_ERR(entry->base);
-		goto fail_ioremap;
+		entry->base = devm_ioremap_resource(dev, &res);
+		if (IS_ERR(entry->base)) {
+			ret = PTR_ERR(entry->base);
+			goto fail_ioremap;
+		}
 	}
 
 	sysfs_bin_attr_init(&entry->pmt_bin_attr);
diff --git a/drivers/platform/x86/intel/pmt/class.h b/drivers/platform/x86/intel/pmt/class.h
index 258cb460e61c..aeb04afb67cf 100644
--- a/drivers/platform/x86/intel/pmt/class.h
+++ b/drivers/platform/x86/intel/pmt/class.h
@@ -48,7 +48,7 @@ struct intel_pmt_entry {
 	const struct attribute_group *attr_grp;
 	struct kobject		*kobj;
 	void __iomem		*disc_table;
-	void __iomem		*base;
+	void __iomem		*base;  /* unused if cb->read_telem is in use */
 	struct pmt_callbacks	*cb;
 	unsigned long		base_addr;
 	size_t			size;
diff --git a/drivers/platform/x86/intel/pmt/telemetry.c b/drivers/platform/x86/intel/pmt/telemetry.c
index 953f35b6daec..5423a4dfce08 100644
--- a/drivers/platform/x86/intel/pmt/telemetry.c
+++ b/drivers/platform/x86/intel/pmt/telemetry.c
@@ -329,6 +329,9 @@ int pmt_telem_read32(struct telem_endpoint *ep, u32 id, u32 *data, u32 count)
 	if (!ep->present)
 		return -ENODEV;
 
+	if (!ep->base)
+		return -EIO;
+
 	offset = SAMPLE_ID_OFFSET32(id);
 	size = ep->header.size;
 
-- 
2.43.0