From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: [PATCH v3] i2c: tegra: Maintain CPU endianness Date: Mon, 26 Jan 2015 19:55:02 +0300 Message-ID: <1422291305-32514-1-git-send-email-digetx@gmail.com> Return-path: Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: digetx-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Wolfram Sang , Stephen Warren , Thierry Reding , Alexandre Courbot , Laxman Dewangan Cc: Ben Dooks , Bob Mottram , linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org Support CPU BE mode by adding endianness conversion for memcpy interactions. Signed-off-by: Dmitry Osipenko Acked-by: Alexandre Courbot --- Changelog: v2: For consistency cpu_to_le32() changed to le32_to_cpu() because i2c_writel() takes BE value in BE CPU mode and value is in LE format. v3: Removed "val = 0;", it turned out it wasn't needed. For some reason it wasn't working at first time, hope it was just me doing something wrong and it's not a heisenbug. I've checked kernel with all memory corruption detection options enabled and it didn't show any problems. drivers/i2c/busses/i2c-tegra.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 28b87e6..29f1433 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -286,6 +286,7 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) if (rx_fifo_avail > 0 && buf_remaining > 0) { BUG_ON(buf_remaining > 3); val = i2c_readl(i2c_dev, I2C_RX_FIFO); + val = cpu_to_le32(val); memcpy(buf, &val, buf_remaining); buf_remaining = 0; rx_fifo_avail--; @@ -344,6 +345,7 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) if (tx_fifo_avail > 0 && buf_remaining > 0) { BUG_ON(buf_remaining > 3); memcpy(&val, buf, buf_remaining); + val = le32_to_cpu(val); /* Again update before writing to FIFO to make sure isr sees. */ i2c_dev->msg_buf_remaining = 0; -- 2.2.1