Hi David, On Thu, 13 Nov 2008 00:53:05 -0800, David Brownell wrote: > On Wednesday 12 November 2008, Jean Delvare wrote: > > David, can we get this patch reviewed and pushed upstream quickly? So > > that I can finally take Manuel's patch adding support for the TMP121. > > Yeah, appended. I made some minor updates, notably: > > - using URLs from National's website > - listing the real name of the eval board (!) > - there is no "D9" bit in any byte; explain that change better > - restore a comment of mine :) > > And different patch comments -- sorry, I lost the first set. > > Jean, I think it's best if you merge this through your tree > along with Manuel's patch. Fine with me, I'll do that right now. > > - Dave > > > ============ CUT HERE > From: Kaiwan N Billimoria <kaiwan at designergraphix.com> > > This fixes a byteswap bug in the LM70 temperature sensor driver, > which was previously covered up by a converse bug in the driver > for the LM70EVAL-LLP board (which is also fixed). > > Other fixes: doc updates, remove an annoying msleep(), and improve > three-wire protocol handling. > > Signed-off-by: Kaiwan N Billimoria <kaiwan at designergraphix.com> > [ dbrownell at users.sourceforge.net: doc and whitespace tweaks ] > Signed-off-by: David Brownell <dbrownell at users.sourceforge.net> > --- > Documentation/hwmon/lm70 | 4 ++++ > Documentation/spi/spi-lm70llp | 10 ++++++++++ > drivers/hwmon/lm70.c | 9 +++++---- > drivers/spi/spi_lm70llp.c | 33 ++++++++++++--------------------- > 4 files changed, 31 insertions(+), 25 deletions(-) > > --- a/Documentation/hwmon/lm70 > +++ b/Documentation/hwmon/lm70 > @@ -25,6 +25,10 @@ complement digital temperature (sent via > driver for interpretation. This driver makes use of the kernel's in-core > SPI support. > > +As a real (in-tree) example of this "SPI protocol driver" interfacing > +with a "SPI master controller driver", see drivers/spi/spi_lm70llp.c > +and its associated documentation. > + > Thanks to > --------- > Jean Delvare <khali at linux-fr.org> for mentoring the hwmon-side driver > --- a/Documentation/spi/spi-lm70llp > +++ b/Documentation/spi/spi-lm70llp > @@ -13,10 +13,20 @@ Description > This driver provides glue code connecting a National Semiconductor LM70 LLP > temperature sensor evaluation board to the kernel's SPI core subsystem. > > +This is a SPI master controller driver. It can be used in conjunction with > +(layered under) the LM70 logical driver (a "SPI protocol driver"). > In effect, this driver turns the parallel port interface on the eval board > into a SPI bus with a single device, which will be driven by the generic > LM70 driver (drivers/hwmon/lm70.c). > > + > +Hardware Interfacing > +-------------------- > +The schematic for this particular board (the LM70EVAL-LLP) is > +available (on page 4) here: > + > + http://www.national.com/appinfo/tempsensors/files/LM70LLPEVALmanual.pdf > + > The hardware interfacing on the LM70 LLP eval board is as follows: > > Parallel LM70 LLP > --- a/drivers/hwmon/lm70.c > +++ b/drivers/hwmon/lm70.c > @@ -65,10 +65,9 @@ static ssize_t lm70_sense_temp(struct de > "spi_write_then_read failed with status %d\n", status); > goto out; > } > - dev_dbg(dev, "rxbuf[1] : 0x%x rxbuf[0] : 0x%x\n", rxbuf[1], rxbuf[0]); > - > - raw = (rxbuf[1] << 8) + rxbuf[0]; > - dev_dbg(dev, "raw=0x%x\n", raw); > + raw = (rxbuf[0] << 8) + rxbuf[1]; > + dev_dbg(dev, "rxbuf[0] : 0x%02x rxbuf[1] : 0x%02x raw=0x%04x\n", > + rxbuf[0], rxbuf[1], raw); > > /* > * The "raw" temperature read into rxbuf[] is a 16-bit signed 2's > @@ -109,6 +108,8 @@ static int __devinit lm70_probe(struct s > if ((spi->mode & (SPI_CPOL|SPI_CPHA)) || !(spi->mode & SPI_3WIRE)) > return -EINVAL; > > + /* NOTE: we assume 8-bit words, and convert to 16 bits manually */ > + > p_lm70 = kzalloc(sizeof *p_lm70, GFP_KERNEL); > if (!p_lm70) > return -ENOMEM; > --- a/drivers/spi/spi_lm70llp.c > +++ b/drivers/spi/spi_lm70llp.c > @@ -1,5 +1,5 @@ > /* > - * spi_lm70llp.c - driver for lm70llp eval board for the LM70 sensor > + * spi_lm70llp.c - driver for LM70EVAL-LLP board for the LM70 sensor > * > * Copyright (C) 2006 Kaiwan N Billimoria <kaiwan at designergraphix.com> > * > @@ -40,8 +40,12 @@ > * master controller driver. The hwmon/lm70 driver is a "SPI protocol > * driver", layered on top of this one and usable without the lm70llp. > * > + * Datasheet and Schematic: > * The LM70 is a temperature sensor chip from National Semiconductor; its > * datasheet is available at http://www.national.com/pf/LM/LM70.html > + * The schematic for this particular board (the LM70EVAL-LLP) is > + * available (on page 4) here: > + * http://www.national.com/appinfo/tempsensors/files/LM70LLPEVALmanual.pdf > * > * Also see Documentation/spi/spi-lm70llp. The SPI<->parport code here is > * (heavily) based on spi-butterfly by David Brownell. > @@ -64,7 +68,7 @@ > * > * Note that parport pin 13 actually gets inverted by the transistor > * arrangement which lets either the parport or the LM70 drive the > - * SI/SO signal. > + * SI/SO signal (see the schematic for details). > */ > > #define DRVNAME "spi-lm70llp" > @@ -106,12 +110,16 @@ static inline struct spi_lm70llp *spidev > static inline void deassertCS(struct spi_lm70llp *pp) > { > u8 data = parport_read_data(pp->port); > + > + data &= ~0x80; /* pull D7/SI-out low while de-asserted */ > parport_write_data(pp->port, data | nCS); > } > > static inline void assertCS(struct spi_lm70llp *pp) > { > u8 data = parport_read_data(pp->port); > + > + data |= 0x80; /* pull D7/SI-out high so lm70 drives SO-in */ > parport_write_data(pp->port, data & ~nCS); > } > > @@ -184,22 +192,7 @@ static void lm70_chipselect(struct spi_d > */ > static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) > { > - static u32 sio=0; > - static int first_time=1; > - > - /* First time: perform SPI bitbang and return the LSB of > - * the result of the SPI call. > - */ > - if (first_time) { > - sio = bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); > - first_time=0; > - return (sio & 0x00ff); > - } > - /* Return the MSB of the result of the SPI call */ > - else { > - first_time=1; > - return (sio >> 8); > - } > + return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); > } > > static void spi_lm70llp_attach(struct parport *p) > @@ -293,10 +286,9 @@ static void spi_lm70llp_attach(struct pa > status = -ENODEV; > goto out_bitbang_stop; > } > - pp->spidev_lm70->bits_per_word = 16; > + pp->spidev_lm70->bits_per_word = 8; > > lm70llp = pp; > - > return; > > out_bitbang_stop: > @@ -326,7 +318,6 @@ static void spi_lm70llp_detach(struct pa > > /* power down */ > parport_write_data(pp->port, 0); > - msleep(10); > > parport_release(pp->pd); > parport_unregister_device(pp->pd); -- Jean Delvare
