On Mon, Apr 18, 2016 at 03:48:37PM -0400, Geoff Lansberry wrote: Hi Geoff. > The current version of the trf7970a driver is missing support for several features that we needed to operate a custom board. > We feel that these features will be useful to others as well, and we want to share them. > > 1: Support for using a gpio as Slave-Select. Our processor has several devices on the spi bus, and we ran out of ss lines. This patch gives TRF7970A the ability to > drive the ss line of the chip from a gpio that is defined in the device tree. > > 2. When reviewing problems we were having in our implementation with TI support staff, they recommended that during initialization, address 0x18 should be written to zero. This patch adds that change > > 3. This existing version of the driver assumes that the crystal driving the trf7970a is 13.56 MHz, because there are several places in the driver code where the rel > ated register is re-written, there is clean way to change to 27.12 MHz. This patch adds a device tree option for 27 MHz and properly or's in changes in locations w > here the register is changed. > > 4. the existing version of the driver assumes that 3.3 volt io is used. The trf7970a has a special register where you can configure it for 1.8 volt io. This patch > adds a device tree option to select that this setting should be made. > > [PATCH 1/4] NFC: trf7970a: Add support for gpio as SS > [PATCH 2/4] NFC: trf7970a: add TI recommended write of zero to > [PATCH 3/4] NFC: trf7970a: add device tree option for 27MHz clock > [PATCH 4/4] NFC: trf7970a: Add device tree option of 1.8 Volt IO I'm on vacation this week but will be back next week. I'll take a look once I'm back. In the meantime, for emails sent to public (techie) list always keep the lines less than 80 characters and always bottom-post (i.e., put your text *underneath* the text that you are responding to). Also, when you change one or more patches in a series, re-submit the entire series with the version number incremented (.e.g., v2, v3, ...) even when you change only one of them. It is a easier for others to know what the latest versions are that way. Thanks, Mark -- -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
