[U-Boot] [PATCH 07/15] iMX28: Add SPI driver

Mike Frysinger
2011-09-12T20:26:11Z

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
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