1. make pxa2xx_spi.c use ssp_request() and ssp_free() to get the common
information of the designated SSP port.
2. remove those IRQ/memory request code, ssp_request() has done that for
the driver
3. the SPI platform device is thus made psuedo, no resource (memory/IRQ)
has to be defined, all will be retreived by ssp_request()
4. introduce ssp_get_clk_div() to handle controller difference in clock
divisor setting
5. use clk_xxx() API for clock enable/disable, and clk_get_rate() to
handle the different SSP clock frequency between different processors
Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Stabilize PIO mode transfers against a range of word sizes and FIFO
thresholds and fixes word size setup/override issues.
1) 16 and 32 bit DMA/PIO transfers broken due to timing differences.
2) Potential for bad transfer counts due to transfer size assumptions.
3) Setup function broken is multiple ways.
4) Per transfer bit_per_word changes break DMA setup in pump_tranfers.
5) False positive timeout are not errors.
6) Changes in pxa2xx_spi_chip not effective in calls to setup.
7) Timeout scaling wrong for PXA255 NSSP.
8) Driver leaks memory while busy during unloading.
Known issues:
SPI_CS_HIGH and SPI_LSB_FIRST settings in struct spi_device are not handled.
Testing:
This patch has been test against the "random length, random bits/word,
random data (verified on loopback) and stepped baud rate by octaves
(3.6MHz to 115kHz)" test. It is robust in PIO mode, using any
combination of tx and rx thresholds, and also in DMA mode (which
internally computes the thresholds).
Much thanks to Ned Forrester for exhaustive reviews, fixes and testing.
The driver is substantially better for his efforts.
Signed-off-by: Stephen Street <stephen@streetfiresound.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix some outstanding issues with the pxa2xx_spi driver when running on a
PXA270:
- Wrong timeout calculation in the setup function due to different
peripheral clock rates in the PXAxxx family.
- Bad handling of SSSR_TFS interrupts in interrupt_transfer function.
- Added locking to interface between the pump_messages workqueue and the
pump_transfers tasklet.
Much thanks to Juergen Beisert for the extensive testing on the PXA270.
Signed-off-by: Stephen Street <stephen@streetfiresound.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This driver turns a PXA2xx synchronous serial port (SSP) into a SPI master
controller (see Documentation/spi/spi_summary). The driver has the following
features:
- Support for any PXA2xx SSP
- SSP PIO and SSP DMA data transfers.
- External and Internal (SSPFRM) chip selects.
- Per slave device (chip) configuration.
- Full suspend, freeze, resume support.
Signed-off-by: Stephen Street <stephen@streetfiresound.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
eric miao