Message ID | 1413744219-6859-4-git-send-email-marex@denx.de |
---|---|
State | Superseded |
Delegated to: | Jagannadha Sutradharudu Teki |
Headers | show |
On 20 October 2014 00:13, Marek Vasut <marex@denx.de> wrote: > The driver contained an endless loop when waiting for TX completion, > this is a bad idea since if the hardware fails, the loop might spin > forever. Add timeout and handle it. > > Signed-off-by: Marek Vasut <marex@denx.de> > Cc: Chin Liang See <clsee@altera.com> > Cc: Dinh Nguyen <dinguyen@altera.com> > Cc: Albert Aribaud <albert.u.boot@aribaud.net> > Cc: Tom Rini <trini@ti.com> > Cc: Wolfgang Denk <wd@denx.de> > Cc: Pavel Machek <pavel@denx.de> > Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com> > --- > drivers/spi/altera_spi.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/drivers/spi/altera_spi.c b/drivers/spi/altera_spi.c > index 373ce30..ee65ec2 100644 > --- a/drivers/spi/altera_spi.c > +++ b/drivers/spi/altera_spi.c > @@ -129,6 +129,8 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, > uint bytes = bitlen / 8; > const uchar *txp = dout; > uchar *rxp = din; > + int timeout = 10000; This could be macro definable. > + uint32_t reg; > > debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__, > slave->bus, slave->cs, bitlen, bytes, flags); > @@ -154,8 +156,16 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, > debug("%s: tx:%x ", __func__, d); > writel(d, &altspi->regs->txdata); > > - while (!(readl(&altspi->regs->status) & ALTERA_SPI_STATUS_RRDY_MSK)) > - ; > + while (--timeout) { > + reg = readl(&altspi->regs->status); > + if (reg & ALTERA_SPI_STATUS_RRDY_MSK) > + break; > + } > + > + if (!timeout) { > + printf("%s: Transmission timed out!\n", __func__); > + goto done; > + } It's better to use tx status check with the help of get_timer() instead of normal while loop. Pls- use the same, we have some drivers who does the same. > > d = readl(&altspi->regs->rxdata); > if (rxp) > -- > 2.1.1 > thanks!
diff --git a/drivers/spi/altera_spi.c b/drivers/spi/altera_spi.c index 373ce30..ee65ec2 100644 --- a/drivers/spi/altera_spi.c +++ b/drivers/spi/altera_spi.c @@ -129,6 +129,8 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, uint bytes = bitlen / 8; const uchar *txp = dout; uchar *rxp = din; + int timeout = 10000; + uint32_t reg; debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__, slave->bus, slave->cs, bitlen, bytes, flags); @@ -154,8 +156,16 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, debug("%s: tx:%x ", __func__, d); writel(d, &altspi->regs->txdata); - while (!(readl(&altspi->regs->status) & ALTERA_SPI_STATUS_RRDY_MSK)) - ; + while (--timeout) { + reg = readl(&altspi->regs->status); + if (reg & ALTERA_SPI_STATUS_RRDY_MSK) + break; + } + + if (!timeout) { + printf("%s: Transmission timed out!\n", __func__); + goto done; + } d = readl(&altspi->regs->rxdata); if (rxp)
The driver contained an endless loop when waiting for TX completion, this is a bad idea since if the hardware fails, the loop might spin forever. Add timeout and handle it. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Chin Liang See <clsee@altera.com> Cc: Dinh Nguyen <dinguyen@altera.com> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: Tom Rini <trini@ti.com> Cc: Wolfgang Denk <wd@denx.de> Cc: Pavel Machek <pavel@denx.de> Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com> --- drivers/spi/altera_spi.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)