On 04/24/2015 08:21 PM, Sören Brinkmann wrote:
Hi Helmut,
On Wed, 2015-04-22 at 11:14AM +0200, Helmut Buchsbaum wrote:
Since SCLK, MISO and MOSI are the only mandatory signals at Zynq's SPI
interfaces, SS0, SS1 and SS2 have to be configured separately as they may
be used as simple GPIO lines.
This, of course, has to be considered in the devicetree, so pin controller
configuration for e.g. an SPI0 using SS0 and SS1 only might look like the
following snippet (derived from the example of chapter "17.5.3
MIO/EMIO" Routing of Zynq-7000 TRM UG585). So MIO20 can now be used
as GPIO instead of being occupied by SPI0 SS2 function:
I think this is very valid and correct. Thanks! One doubt I have though:
[...]
@@ -548,10 +591,20 @@ static const char * const qspi0_groups[] = {"qspi0_0_grp"};
static const char * const qspi1_groups[] = {"qspi0_1_grp"};
static const char * const qspi_fbclk_groups[] = {"qspi_fbclk_grp"};
static const char * const qspi_cs1_groups[] = {"qspi_cs1_grp"};
-static const char * const spi0_groups[] = {"spi0_0_grp", "spi0_1_grp",
- "spi0_2_grp"};
-static const char * const spi1_groups[] = {"spi1_0_grp", "spi1_1_grp",
- "spi1_2_grp", "spi1_3_grp"};
+static const char * const spi0_groups[] = {"spi0_0_grp", "spi0_0_ss0_grp",
+ "spi0_0_ss1_grp", "spi0_0_ss2_grp",
+ "spi0_1_grp", "spi0_1_ss0_grp",
+ "spi0_1_ss1_grp", "spi0_1_ss2_grp",
+ "spi0_2_grp", "spi0_2_ss0_grp",
+ "spi0_2_ss1_grp", "spi0_2_ss2_grp"};
+static const char * const spi1_groups[] = {"spi1_0_grp", "spi1_0_ss0_grp",
+ "spi1_0_ss1_grp", "spi1_0_ss2_grp",
+ "spi1_1_grp", "spi1_1_ss0_grp",
+ "spi1_1_ss1_grp", "spi1_1_ss2_grp",
+ "spi1_2_grp", "spi1_2_ss0_grp",
+ "spi1_2_ss1_grp", "spi1_2_ss2_grp",
+ "spi1_3_grp", "spi1_3_ss0_grp",
+ "spi1_3_ss1_grp", "spi1_3_ss2_grp"};
Can we add this to the spiX groups or do we need individual
spix_ss_groups[] arrays? E.g. for the SD card detect signal and similar
we have individual groups arrays.
Sören
You're right. The cleaner solution is to keep the slave select groups in
separate spix_ss_groups[] arrays. This also results in additional
spix_ss pinmux functions. As a result this will be rather similar to the
PC, WP and CD signals for SDIO. I'll change that and rework my patch.
Thanks,
Helmut
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