[U-Boot] [PATCH 07/15] iMX28: Add SPI driver
Marek Vasut
marek.vasut at gmail.com
Tue Sep 13 00:45:14 CEST 2011
On Monday, September 12, 2011 10:26:11 PM Mike Frysinger wrote:
> On Monday, September 12, 2011 13:42:22 Marek Vasut wrote:
> > On Monday, September 12, 2011 06:35:10 PM Mike Frysinger wrote:
> > > On Monday, September 12, 2011 00:06:41 Marek Vasut wrote:
> > > > +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
> > > > + unsigned int max_hz, unsigned int
mode)
> > > > +{
> > > > +
> > > > + mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
> > > > +
> > > > + writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT, &ssp_regs->hw_ssp_ctrl0);
> > > > +
> > > > + reg = SSP_CTRL1_SSP_MODE_SPI | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
> > > > + reg |= (mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;
> > > > + reg |= (mode & SPI_CPHA) ? SSP_CTRL1_PHASE : 0;
> > > > + writel(reg, &ssp_regs->hw_ssp_ctrl1);
> > > > +
> > > > + writel(0, &ssp_regs->hw_ssp_cmd0);
> > > > +
> > > > + mx28_set_ssp_busclock(bus, max_hz / 1000);
> > >
> > > these steps should be done in the claim_bus func
> >
> > I don't think so ... I need to access max_hz and mode. This seems more
> > fitting to me.
>
> that's not how the API works. you create clients, then you acquire the bus
> for a specific client, do a transfer, and then release it. your bus breaks
> with the trivial case:
> - setup slave A
> - setup slave B
> - claim bus for slave A
> - transfer with slave A <- uses settings from slave B
> -mike
Thanks for clearing this, fixed in V3
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