[PATCH v2 26/27] drm/tegra: Add DSI support

[Stephen Warren]

On 10/14/2013 07:55 AM, Thierry Reding wrote:
> On Fri, Oct 11, 2013 at 04:43:35PM -0600, Stephen Warren wrote:
>> On 10/07/2013 02:34 AM, Thierry Reding wrote:
>>> This commit adds support for both DSI outputs found on Tegra. Only very
>>> minimal functionality is implemented, so advanced features like ganged
>>> mode won't work.
>>>
>>> Due to the lack of other test hardware, some sections of the driver are
>>> hardcoded to work with Dalmore.
>>
>>> diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
>>
>>> +static int tegra_dsi_show_regs(struct seq_file *s, void *data)
>>> +{
>>> +	struct drm_info_node *node = s->private;
>>> +	struct tegra_dsi *dsi = node->info_ent->data;
>>> +
>>> +#define DUMP_REG(name)						\
>>> +	seq_printf(s, "%-32s %#05x %08lx\n", #name, name,	\
>>> +		   tegra_dsi_readl(dsi, name))
>>> +
>>> +	DUMP_REG(DSI_INCR_SYNCPT);
>>
>> Does it make sense to use an MMIO regmap instead? That way, you get all
>> the debugfs files for free...
> 
> As far as I know, regmap doesn't give you the symbolic names for the
> registers. I find that a rather useful feature because it allows to
> easily compare the registers to the ones in our downstream kernels.

True. However, we should really be writing user-space scripts to encode
that information. Such a script could be useful e.g. if reading the
information directly from /dev/mem or JTAG too, and bloating the kernel
with debug strings doesn't seem like a great idea.