Re: [alsa-devel] [PATCH v2 09/13] OMAP: McBSP: use omap_device APIs to modify SYSCONFIG

Hi,

On 01/31/2011 04:50 PM, ext Kishon Vijay Abraham I wrote:

McBSP2/3 in OMAP3 has sidetone feature which requires autoidle to be disabled before starting the sidetone. Also SYSCONFIG register has to be set with smart idle or no idle depending on the dma op mode (threshold or element sync). For doing these operations dynamically at runtime, omap_device APIs are used to modify SYSCONFIG register.

Signed-off-by: Kishon Vijay Abraham I kishon@ti.com

arch/arm/plat-omap/mcbsp.c | 66 +++++++++++++++++++++++-------------------- 1 files changed, 35 insertions(+), 31 deletions(-)

diff --git a/arch/arm/plat-omap/mcbsp.c b/arch/arm/plat-omap/mcbsp.c

...

static inline void omap34xx_mcbsp_request(struct omap_mcbsp *mcbsp) {

• struct omap_device *od;
• od = find_omap_device_by_dev(mcbsp->dev); /*
  • Enable wakup behavior, smart idle and all wakeups
  • REVISIT: some wakeups may be unnecessary
  */ if (cpu_is_omap34xx() || cpu_is_omap44xx()) {

• u16 syscon;
  

• syscon = MCBSP_READ(mcbsp, SYSCON);
  

• syscon &= ~(ENAWAKEUP | SIDLEMODE(0x03) | CLOCKACTIVITY(0x03));
  

• if (mcbsp->dma_op_mode == MCBSP_DMA_MODE_THRESHOLD) {
  

• 	syscon |= (ENAWAKEUP | SIDLEMODE(0x02) |
  

• 			CLOCKACTIVITY(0x02));
  

• if (mcbsp->dma_op_mode != MCBSP_DMA_MODE_THRESHOLD)
  

• 	omap_device_noidle(od);
  

• else
  

Would it make sense to call here: omap_device_smartidle(od); ? What happens, if we configure McBSP to element mode, play a sample, configure it to threshold? I think we should explicitly as for smartidle, when we suppose to be in smartidle.

	MCBSP_WRITE(mcbsp, WAKEUPEN, XRDYEN | RRDYEN);

• } else {
  

• 	syscon |= SIDLEMODE(0x01);
  

• }
  

• MCBSP_WRITE(mcbsp, SYSCON, syscon);
  

  }

}

static inline void omap34xx_mcbsp_free(struct omap_mcbsp *mcbsp) {

• struct omap_device *od;
• od = find_omap_device_by_dev(mcbsp->dev);
• /*
  • Disable wakup behavior, smart idle and all wakeups
  */ if (cpu_is_omap34xx() || cpu_is_omap44xx()) {

• u16 syscon;
  

• syscon = MCBSP_READ(mcbsp, SYSCON);
  

• syscon &= ~(ENAWAKEUP | SIDLEMODE(0x03) | CLOCKACTIVITY(0x03));
  

  /*
  • HW bug workaround - If no_idle mode is taken, we need to
  • go to smart_idle before going to always_idle, or the
  • device will not hit retention anymore.
  */

• syscon |= SIDLEMODE(0x02);
  

• MCBSP_WRITE(mcbsp, SYSCON, syscon);
  

• syscon &= ~(SIDLEMODE(0x03));
  

• MCBSP_WRITE(mcbsp, SYSCON, syscon);
  

• omap_device_default_idle(od);
  

  MCBSP_WRITE(mcbsp, WAKEUPEN, 0);

Hrm, it would be better to do it as the comment said: omap_device_smartidle(od); omap_device_forceidle(od);

BTW: what is the default_idle in case of McBSP?