Hi Paul
Patchset looks good, feel free to add my ack
On Sun, Jan 22, 2012 at 01:26:23PM -0700, Paul Walmsley (paul@xxxxxxxxx) wrote:
>
> HDQ/1-wire registers are 32 bits long, even if the register contents
> fit into 8 bits, so accesses must be 32-bit aligned. Evidently the
> OMAP2/3 interconnects allowed the driver to get away with 8 bit accesses,
> but the OMAP4 puts a stop to that:
>
> [ 1.488800] Driver for 1-wire Dallas network protocol.
> [ 1.495025] Bad mode in data abort handler detected
> [ 1.500122] Internal error: Oops - bad mode: 0 [#1] SMP
> [ 1.505615] Modules linked in:
> [ 1.508819] CPU: 0 Not tainted (3.3.0-rc1-00008-g45030e9 #992)
> [ 1.515289] PC is at 0xffff0018
> [ 1.518615] LR is at omap_hdq_probe+0xd4/0x2cc
>
> The OMAP4430 ES2 Rev X TRM does warn about this restriction in section
> 23.2.6.2 "HDQ/1-Wire Registers".
>
> Fixes the crash on OMAP4430 ES2 Pandaboard. Tested also on OMAP34xx and
> OMAP2420; it seems to work fine on those chips, although due to the lack
> of boards with HDQ/1-wire devices here, a more indepth test was not
> possible.
>
> ---
> Intended for the v3.4 merge window.
>
> drivers/w1/masters/omap_hdq.c | 8 ++++----
> 1 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/w1/masters/omap_hdq.c b/drivers/w1/masters/omap_hdq.c
> index 63e3eda..291897c 100644
> --- a/drivers/w1/masters/omap_hdq.c
> +++ b/drivers/w1/masters/omap_hdq.c
> @@ -100,20 +100,20 @@ static struct w1_bus_master omap_w1_master = {
> /* HDQ register I/O routines */
> static inline u8 hdq_reg_in(struct hdq_data *hdq_data, u32 offset)
> {
> - return __raw_readb(hdq_data->hdq_base + offset);
> + return __raw_readl(hdq_data->hdq_base + offset);
> }
>
> static inline void hdq_reg_out(struct hdq_data *hdq_data, u32 offset, u8 val)
> {
> - __raw_writeb(val, hdq_data->hdq_base + offset);
> + __raw_writel(val, hdq_data->hdq_base + offset);
> }
>
> static inline u8 hdq_reg_merge(struct hdq_data *hdq_data, u32 offset,
> u8 val, u8 mask)
> {
> - u8 new_val = (__raw_readb(hdq_data->hdq_base + offset) & ~mask)
> + u8 new_val = (__raw_readl(hdq_data->hdq_base + offset) & ~mask)
> | (val & mask);
> - __raw_writeb(new_val, hdq_data->hdq_base + offset);
> + __raw_writel(new_val, hdq_data->hdq_base + offset);
>
> return new_val;
> }
> --
> 1.7.8.3
--
Evgeniy Polyakov
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