From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 1981D1A070B for ; Fri, 3 Oct 2014 17:12:36 +1000 (EST) Message-ID: <1412320345.30859.9.camel@pasglop> Subject: [PATCH] powerpc/powernv: Fix endian bug in LPC bus debugfs accessors From: Benjamin Herrenschmidt To: linuxppc-dev Date: Fri, 03 Oct 2014 17:12:25 +1000 Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: Anton Blanchard List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 CC: --- 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);