[PATCH] powerpc/powernv: Fix endian bug in LPC bus debugfs accessors
DORMANTno replies
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2014-10-03 07:12:36
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
When reading from the LPC, the OPAL FW calls return the value via pointer to a uint32_t which is always returned big endian. Our internal inb/outb implementation byteswaps that fine but our debugfs code is still broken. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: <redacted> ---
diff --git a/arch/powerpc/platforms/powernv/opal-lpc.c b/arch/powerpc/platforms/powernv/opal-lpc.c
index ad4b31d..dd2c285 100644
--- a/arch/powerpc/platforms/powernv/opal-lpc.c
+++ b/arch/powerpc/platforms/powernv/opal-lpc.c@@ -191,6 +191,7 @@ static ssize_t lpc_debug_read(struct file *filp, char __user *ubuf, { struct lpc_debugfs_entry *lpc = filp->private_data; u32 data, pos, len, todo; + __be32 bedata; int rc; if (!access_ok(VERIFY_WRITE, ubuf, count))
@@ -213,9 +214,10 @@ static ssize_t lpc_debug_read(struct file *filp, char __user *ubuf, len = 2; } rc = opal_lpc_read(opal_lpc_chip_id, lpc->lpc_type, pos, - &data, len); + &bedata, len); if (rc) return -ENXIO; + data = be32_to_cpu(bedata); switch(len) { case 4: rc = __put_user((u32)data, (u32 __user *)ubuf);