Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / drivers / edac / edac_mc_sysfs.c

diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
index dce61f7ba38ba9094d9e300f62fe542312a623b1..39d97cfdf58cee45f3cf2c4df087cdbfa4707089 100644 (file)
--- a/drivers/edac/edac_mc_sysfs.c
+++ b/drivers/edac/edac_mc_sysfs.c
@@ -436,56 +436,55 @@ static ssize_t mci_reset_counters_store(struct mem_ctl_info *mci,
        return count;
 }
 
-/* memory scrubbing */
+/* Memory scrubbing interface:
+ *
+ * A MC driver can limit the scrubbing bandwidth based on the CPU type.
+ * Therefore, ->set_sdram_scrub_rate should be made to return the actual
+ * bandwidth that is accepted or 0 when scrubbing is to be disabled.
+ *
+ * Negative value still means that an error has occurred while setting
+ * the scrub rate.
+ */
 static ssize_t mci_sdram_scrub_rate_store(struct mem_ctl_info *mci,
                                          const char *data, size_t count)
 {
        unsigned long bandwidth = 0;
-       int err;
+       int new_bw = 0;
 
-       if (!mci->set_sdram_scrub_rate) {
-               edac_printk(KERN_WARNING, EDAC_MC,
-                           "Memory scrub rate setting not implemented!\n");
+       if (!mci->set_sdram_scrub_rate)
                return -EINVAL;
-       }
 
        if (strict_strtoul(data, 10, &bandwidth) < 0)
                return -EINVAL;
 
-       err = mci->set_sdram_scrub_rate(mci, (u32)bandwidth);
-       if (err) {
-               edac_printk(KERN_DEBUG, EDAC_MC,
-                           "Failed setting scrub rate to %lu\n", bandwidth);
-               return -EINVAL;
-       }
-       else {
-               edac_printk(KERN_DEBUG, EDAC_MC,
-                           "Scrub rate set to: %lu\n", bandwidth);
+       new_bw = mci->set_sdram_scrub_rate(mci, bandwidth);
+       if (new_bw >= 0) {
+               edac_printk(KERN_DEBUG, EDAC_MC, "Scrub rate set to %d\n", new_bw);
                return count;
        }
+
+       edac_printk(KERN_DEBUG, EDAC_MC, "Error setting scrub rate to: %lu\n", bandwidth);
+       return -EINVAL;
 }
 
+/*
+ * ->get_sdram_scrub_rate() return value semantics same as above.
+ */
 static ssize_t mci_sdram_scrub_rate_show(struct mem_ctl_info *mci, char *data)
 {
-       u32 bandwidth = 0;
-       int err;
+       int bandwidth = 0;
 
-       if (!mci->get_sdram_scrub_rate) {
-               edac_printk(KERN_WARNING, EDAC_MC,
-                           "Memory scrub rate reading not implemented\n");
+       if (!mci->get_sdram_scrub_rate)
                return -EINVAL;
-       }
 
-       err = mci->get_sdram_scrub_rate(mci, &bandwidth);
-       if (err) {
+       bandwidth = mci->get_sdram_scrub_rate(mci);
+       if (bandwidth < 0) {
                edac_printk(KERN_DEBUG, EDAC_MC, "Error reading scrub rate\n");
-               return err;
-       }
-       else {
-               edac_printk(KERN_DEBUG, EDAC_MC,
-                           "Read scrub rate: %d\n", bandwidth);
-               return sprintf(data, "%d\n", bandwidth);
+               return bandwidth;
        }
+
+       edac_printk(KERN_DEBUG, EDAC_MC, "Read scrub rate: %d\n", bandwidth);
+       return sprintf(data, "%d\n", bandwidth);
 }
 
 /* default attribute files for the MCI object */