[PATCH v10 1/8] spi: Add multi-cs memories support in SPI core
Stefan Binding
sbinding at opensource.cirrus.com
Fri Nov 24 09:33:47 PST 2023
> -----Original Message-----
> From: Mahapatra, Amit Kumar <amit.kumar-mahapatra at amd.com>
> Sent: Wednesday, November 22, 2023 1:23 PM
> To: Stefan Binding <sbinding at opensource.cirrus.com>;
> broonie at kernel.org; tudor.ambarus at linaro.org; pratyush at kernel.org;
> miquel.raynal at bootlin.com; richard at nod.at; vigneshr at ti.com
> Cc: linux-spi at vger.kernel.org; linux-kernel at vger.kernel.org;
> michael at walle.cc; linux-mtd at lists.infradead.org;
> nicolas.ferre at microchip.com; alexandre.belloni at bootlin.com;
> claudiu.beznea at tuxon.dev; Simek, Michal <michal.simek at amd.com>;
> linux-arm-kernel at lists.infradead.org; git (AMD-Xilinx) <git at amd.com>;
> amitrkcian2002 at gmail.com; patches at opensource.cirrus.com
> Subject: RE: [PATCH v10 1/8] spi: Add multi-cs memories support in SPI
> core
>
>
>
> > -----Original Message-----
> > From: Stefan Binding <sbinding at opensource.cirrus.com>
> > Sent: Wednesday, November 22, 2023 4:51 PM
> > To: Mahapatra, Amit Kumar <amit.kumar-mahapatra at amd.com>;
> > broonie at kernel.org; tudor.ambarus at linaro.org; pratyush at kernel.org;
> > miquel.raynal at bootlin.com; richard at nod.at; vigneshr at ti.com
> > Cc: linux-spi at vger.kernel.org; linux-kernel at vger.kernel.org;
> > michael at walle.cc; linux-mtd at lists.infradead.org;
> > nicolas.ferre at microchip.com; alexandre.belloni at bootlin.com;
> > claudiu.beznea at tuxon.dev; Simek, Michal <michal.simek at amd.com>;
> linux-
> > arm-kernel at lists.infradead.org; git (AMD-Xilinx) <git at amd.com>;
> > amitrkcian2002 at gmail.com; patches at opensource.cirrus.com
> > Subject: Re: [PATCH v10 1/8] spi: Add multi-cs memories support in SPI
> core
> >
> >
> > On 21/11/2023 19:18, Mahapatra, Amit Kumar wrote:
> > > Hello Stefan,
> > >
> > >> -----Original Message-----
> > >> From: Stefan Binding <sbinding at opensource.cirrus.com>
> > >> Sent: Tuesday, November 21, 2023 11:07 PM
> > >> To: Mahapatra, Amit Kumar <amit.kumar-mahapatra at amd.com>;
> > >> broonie at kernel.org; tudor.ambarus at linaro.org;
> pratyush at kernel.org;
> > >> miquel.raynal at bootlin.com; richard at nod.at; vigneshr at ti.com
> > >> Cc: linux-spi at vger.kernel.org; linux-kernel at vger.kernel.org;
> > >> michael at walle.cc; linux-mtd at lists.infradead.org;
> > >> nicolas.ferre at microchip.com; alexandre.belloni at bootlin.com;
> > >> claudiu.beznea at tuxon.dev; Simek, Michal
> <michal.simek at amd.com>;
> > >> linux- arm-kernel at lists.infradead.org; git (AMD-Xilinx)
> > >> <git at amd.com>; amitrkcian2002 at gmail.com;
> > >> patches at opensource.cirrus.com
> > >> Subject: Re: [PATCH v10 1/8] spi: Add multi-cs memories support in
> > >> SPI core
> > >>
> > >>
> > >> On 21/11/2023 16:35, Mahapatra, Amit Kumar wrote:
> > >>> Hello Stefan,
> > >>>
> > >>>> -----Original Message-----
> > >>>> From: Stefan Binding <sbinding at opensource.cirrus.com>
> > >>>> Sent: Tuesday, November 21, 2023 7:28 PM
> > >>>> To: Mahapatra, Amit Kumar <amit.kumar-mahapatra at amd.com>;
> > >>>> broonie at kernel.org; tudor.ambarus at linaro.org;
> pratyush at kernel.org;
> > >>>> miquel.raynal at bootlin.com; richard at nod.at; vigneshr at ti.com
> > >>>> Cc: linux-spi at vger.kernel.org; linux-kernel at vger.kernel.org;
> > >>>> michael at walle.cc; linux-mtd at lists.infradead.org;
> > >>>> nicolas.ferre at microchip.com; alexandre.belloni at bootlin.com;
> > >>>> claudiu.beznea at tuxon.dev; Simek, Michal
> <michal.simek at amd.com>;
> > >>>> linux- arm-kernel at lists.infradead.org; git (AMD-Xilinx)
> > >>>> <git at amd.com>; amitrkcian2002 at gmail.com;
> > >>>> patches at opensource.cirrus.com
> > >>>> Subject: Re: [PATCH v10 1/8] spi: Add multi-cs memories support in
> > >>>> SPI core
> > >>>>
> > >>>>
> > >>>> On 21/11/2023 07:39, Mahapatra, Amit Kumar wrote:
> > >>>>> Hello Stefan,
> > >>>>>
> > >>>>>> -----Original Message-----
> > >>>>>> From: Stefan Binding <sbinding at opensource.cirrus.com>
> > >>>>>> Sent: Monday, November 20, 2023 8:00 PM
> > >>>>>> To: Mahapatra, Amit Kumar <amit.kumar-
> mahapatra at amd.com>;
> > >>>>>> broonie at kernel.org; tudor.ambarus at linaro.org;
> > >>>>>> pratyush at kernel.org; miquel.raynal at bootlin.com;
> richard at nod.at;
> > >>>>>> vigneshr at ti.com
> > >>>>>> Cc: linux-spi at vger.kernel.org; linux-kernel at vger.kernel.org;
> > >>>>>> michael at walle.cc; linux-mtd at lists.infradead.org;
> > >>>>>> nicolas.ferre at microchip.com; alexandre.belloni at bootlin.com;
> > >>>>>> claudiu.beznea at tuxon.dev; Simek, Michal
> > <michal.simek at amd.com>;
> > >>>>>> linux- arm-kernel at lists.infradead.org; git (AMD-Xilinx)
> > >>>>>> <git at amd.com>; amitrkcian2002 at gmail.com;
> > >>>>>> patches at opensource.cirrus.com
> > >>>>>> Subject: Re: [PATCH v10 1/8] spi: Add multi-cs memories support
> > >>>>>> in SPI core
> > >>>>>>
> > >>>>>>
> > >>>>>> On 18/11/2023 13:54, Amit Kumar Mahapatra wrote:
> > >>>>>>> AMD-Xilinx GQSPI controller has two advanced mode that
> allows
> > >>>>>>> the controller to consider two flashes as one single device.
> > >>>>>>>
> > >>>>>>> One of these two mode is the parallel mode in which each byte
> of
> > >>>>>>> data is stored in both devices, the even bits in the lower flash
> > >>>>>>> & the odd bits in the upper flash. The byte split is
> > >>>>>>> automatically handled by the QSPI controller.
> > >>>>>>>
> > >>>>>>> The other mode is the stacked mode in which both the flashes
> > >>>>>>> share the same SPI bus but each of the device contain half of
> the
> > data.
> > >>>>>>> In this mode, the controller does not follow CS requests but
> > >>>>>>> instead internally wires the two CS levels with the value of the
> > >>>>>>> most significant
> > >>>>>> address bit.
> > >>>>>>> For supporting both these modes SPI core need to be updated
> for
> > >>>>>>> providing multiple CS for a single SPI device.
> > >>>>>>>
> > >>>>>>> For adding multi CS support the SPI device need to be aware of
> > >>>>>>> all the CS values. So, the "chip_select" member in the
> > >>>>>>> spi_device structure is now an array that holds all the CS values.
> > >>>>>>>
> > >>>>>>> spi_device structure now has a "cs_index_mask" member. This
> acts
> > >>>>>>> as an index to the chip_select array. If nth bit of
> > >>>>>>> spi->cs_index_mask is set then the driver would assert spi-
> > >>> chip_select[n].
> > >>>>>>> In parallel mode all the chip selects are asserted/de-asserted
> > >>>>>>> simultaneously and each byte of data is stored in both devices,
> > >>>>>>> the even bits in one, the odd bits in the other. The split is
> > >>>>>>> automatically handled by the GQSPI controller. The GQSPI
> > >>>>>>> controller supports a maximum of two flashes connected in
> > >>>>>>> parallel mode. A SPI_CONTROLLER_MULTI_CS flag bit is added
> in
> > >>>>>>> the spi controller flags, through ctlr->flags the spi core will
> > >>>>>>> make sure that the controller is capable of handling multiple
> chip
> > selects at once.
> > >>>>>>>
> > >>>>>>> For supporting multiple CS via GPIO the cs_gpiod member of the
> > >>>>>>> spi_device structure is now an array that holds the gpio
> > >>>>>>> descriptor for each chipselect.
> > >>>>>>>
> > >>>>>>> CS GPIO is not tested due to unavailability of necessary
> > >>>>>>> hardware
> > >> setup.
> > >>>>>>> Signed-off-by: Amit Kumar Mahapatra <amit.kumar-
> > >>>> mahapatra at amd.com>
> > >>>>>>> ---
> > >>>>>>> Hello @Stefen,
> > >>>>>>> We restructured the SPI core implementation, for handling
> > >>>>>>> arbitrary number of devices connected in parallel(multi-cs) or
> > >>>>>>> stacked
> > >> mode.
> > >>>>>>> We have tested this updated patch on native-cs setup but
> > >>>>>>> couldn't test cs-gpio due to unavailability of a proper setup.
> > >>>>>>> If possible, could you please retest the cs-gpio use case with
> > >>>>>>> this updated patch and provide
> > >>>>>> your feedback.
> > >>>>>>
> > >>>>>> Hi,
> > >>>>>>
> > >>>>>> I tested this chain on 2 different systems using GPIOs as chip
> > >>>>>> selects, and see the same error on both:
> > >>>>>> [ 2.842045] pxa2xx-spi pxa2xx-spi.6: chipselect 0 already in
> > >>>>>> use
> > >>>>>>
> > >>>>>> Let me know if you need any further testing.
> > >>>>>>
> > >>>>>> Thanks,
> > >>>>>>
> > >>>>>> Stefan Binding
> > >>>>>>
> > >>>>>>> ---
> > >>>>>>> drivers/spi/spi.c | 192
> +++++++++++++++++++++++++++++++---
> > ----
> > >> --
> > >>>>>>> include/linux/spi/spi.h | 51 ++++++++---
> > >>>>>>> 2 files changed, 191 insertions(+), 52 deletions(-)
> > >>>>>>>
> > >>>>>>> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index
> > >>>>>>> 8ead7acb99f3..ff66147ba95f 100644
> > >>>>>>> --- a/drivers/spi/spi.c
> > >>>>>>> +++ b/drivers/spi/spi.c
> > >>>>>>> @@ -612,10 +612,21 @@ static int spi_dev_check(struct
> device
> > >>>>>>> *dev, void
> > >>>>>> *data)
> > >>>>>>> {
> > >>>>>>> struct spi_device *spi = to_spi_device(dev);
> > >>>>>>> struct spi_device *new_spi = data;
> > >>>>>>> -
> > >>>>>>> - if (spi->controller == new_spi->controller &&
> > >>>>>>> - spi_get_chipselect(spi, 0) ==
> spi_get_chipselect(new_spi, 0))
> > >>>>>>> - return -EBUSY;
> > >>>>>>> + int idx, nw_idx;
> > >>>>>>> + u8 cs, cs_nw;
> > >>>>>>> +
> > >>>>>>> + if (spi->controller == new_spi->controller) {
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>>>>>> + cs = spi_get_chipselect(spi, idx);
> > >>>>>>> + for (nw_idx = 0; nw_idx <
> SPI_CS_CNT_MAX;
> > >>>>>> nw_idx++) {
> > >>>>>>> + cs_nw = spi_get_chipselect(spi,
> > >> nw_idx);
> > >>>>> Thank you for dedicating your time to test my patch.
> > >>>>> As per my analysis the error is reported from here as we are
> > >>>>> supplying the former SPI device structure to retrieve the CS value
> > >>>>> for the new SPI devices.
> > >>>>> To fix this, could you kindly substitute the above line with
> > >>>>>
> > >>>>> cs_nw = spi_get_chipselect(new_spi, nw_idx);
> > >>>>>
> > >>>>> and rerun your tests?
> > >>>>> If it works correctly, I will incorporate this fix into my
> > >>>>> upcoming series.
> > >>>>>
> > >>>>> Regards,
> > >>>>> Amit
> > >> Hi,
> > >>
> > >> I've attached my log.
> > >> I notice that you add a print to of_spi_parse_dt, however since the
> > >> laptop I am using is an x86 laptop, it uses ACPI rather than OF, and
> > >> I don't think this function isnt even compiled in.
> > > That’s correct, I missed it.
> > > Upon reviewing the logs, I discovered that in the ACPI flow, I am not
> > > initializing the unused CS[] to FF, as I am doing in the OF flow.
> > > Consequently, in the ACPI flow, all the unused CS[] are automatically
> > > initialized to 0. During the __spi_add_device process, the SPI core
> > > faces difficulty distinguishing between a valid CS value of 0 and an
> > > unused CS value of 0, leading to a failure in the driver probe.
> > >
> > > Incorporating the following modifications should resolve this issue.
> > > Kindly apply these changes on top of 1/8 and re-run the test.
> > >
> > > diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index
> > > ff66147ba95f..d0301c17d4f8 100644
> > > --- a/drivers/spi/spi.c
> > > +++ b/drivers/spi/spi.c
> > > @@ -619,7 +619,7 @@ static int spi_dev_check(struct device *dev,
> void
> > *data)
> > > for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > > cs = spi_get_chipselect(spi, idx);
> > > for (nw_idx = 0; nw_idx < SPI_CS_CNT_MAX; nw_idx++) {
> > > - cs_nw = spi_get_chipselect(spi, nw_idx);
> > > + cs_nw = spi_get_chipselect(new_spi,
> > > + nw_idx);
> > > if (cs != 0xFF && cs_nw != 0xFF && cs == cs_nw) {
> > > dev_err(dev, "chipselect %d already in use\n",
> > cs_nw);
> > > return -EBUSY; @@ -764,6
> > > +764,7 @@ struct spi_device *spi_new_device(struct spi_controller
> *ctlr,
> > > {
> > > struct spi_device *proxy;
> > > int status;
> > > + u8 idx;
> > >
> > > /*
> > > * NOTE: caller did any chip->bus_num checks necessary.
> > > @@ -779,6 +780,9 @@ struct spi_device *spi_new_device(struct
> > > spi_controller *ctlr,
> > >
> > > WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias));
> > >
> > > + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > > + spi_set_chipselect(proxy, idx, 0xFF);
> > > +
> > > spi_set_chipselect(proxy, 0, chip->chip_select);
> > > proxy->max_speed_hz = chip->max_speed_hz;
> > > proxy->mode = chip->mode;
> > > @@ -2514,6 +2518,7 @@ struct spi_device
> > *spi_new_ancillary_device(struct spi_device *spi,
> > > struct spi_controller *ctlr = spi->controller;
> > > struct spi_device *ancillary;
> > > int rc = 0;
> > > + u8 idx;
> > >
> > > /* Alloc an spi_device */
> > > ancillary = spi_alloc_device(ctlr); @@ -2524,6 +2529,9 @@
> > > struct spi_device *spi_new_ancillary_device(struct spi_device *spi,
> > >
> > > strscpy(ancillary->modalias, "dummy",
> > > sizeof(ancillary->modalias));
> > >
> > > + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > > + spi_set_chipselect(ancillary, idx, 0xFF);
> > > +
> > > /* Use provided chip-select for ancillary device */
> > > spi_set_chipselect(ancillary, 0, chip_select);
> > >
> > > @@ -2732,6 +2740,7 @@ struct spi_device
> *acpi_spi_device_alloc(struct
> > spi_controller *ctlr,
> > > struct acpi_spi_lookup lookup = {};
> > > struct spi_device *spi;
> > > int ret;
> > > + u8 idx;
> > >
> > > if (!ctlr && index == -1)
> > > return ERR_PTR(-EINVAL); @@ -2767,6 +2776,9 @@ struct
> > > spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr,
> > > return ERR_PTR(-ENOMEM);
> > > }
> > >
> > > + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > > + spi_set_chipselect(spi, idx, 0xFF);
> > > +
> > > ACPI_COMPANION_SET(&spi->dev, adev);
> > > spi->max_speed_hz = lookup.max_speed_hz;
> > > spi->mode |= lookup.mode;
> > >
> > > Regards,
> > > Amit
> > >
> >
> > Hi,
> >
> > I no longer see that error, or any errors printed from SPI, however, all of
> the
> > transactions are now broken.
> > Every transaction seems to read back 0x0, on all SPI devices, whether
> native
> > CS or GPIO CS, and I dont see it toggling the CS GPIO anymore.
>
> I believe the issue stems from the fact that in the ACPI patch,
> spi->cs_index_mask is not set to 0x01. As a result, in spi_set_cs,
> it fails to meet the condition that governs the CS asset code snippet.
> In the following code diff, I've included the necessary fix along with
> the earlier changes on top of 1/8. I've also included a couple of debug
> prints to aid in further debugging in case my analysis is incorrect.
> Please apply these changes on top of 1/8 and re-run the test.
>
Hi,
I've tested this on several laptops, and it all seems to work now.
Tested-by: Stefan Binding <sbinding at opensource.cirrus.com>
Thanks,
Stefan
> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
> index ff66147ba95f..b2e035c3d494 100644
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -619,7 +619,7 @@ static int spi_dev_check(struct device *dev, void
> *data)
> for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> cs = spi_get_chipselect(spi, idx);
> for (nw_idx = 0; nw_idx < SPI_CS_CNT_MAX; nw_idx++) {
> - cs_nw = spi_get_chipselect(spi, nw_idx);
> + cs_nw = spi_get_chipselect(new_spi, nw_idx);
> if (cs != 0xFF && cs_nw != 0xFF && cs == cs_nw) {
> dev_err(dev, "chipselect %d already in use\n",
> cs_nw);
> return -EBUSY;
> @@ -764,6 +764,7 @@ struct spi_device *spi_new_device(struct
> spi_controller *ctlr,
> {
> struct spi_device *proxy;
> int status;
> + u8 idx;
>
> /*
> * NOTE: caller did any chip->bus_num checks necessary.
> @@ -779,6 +780,9 @@ struct spi_device *spi_new_device(struct
> spi_controller *ctlr,
>
> WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias));
>
> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> + spi_set_chipselect(proxy, idx, 0xFF);
> +
> spi_set_chipselect(proxy, 0, chip->chip_select);
> proxy->max_speed_hz = chip->max_speed_hz;
> proxy->mode = chip->mode;
> @@ -787,6 +791,7 @@ struct spi_device *spi_new_device(struct
> spi_controller *ctlr,
> proxy->dev.platform_data = (void *) chip->platform_data;
> proxy->controller_data = chip->controller_data;
> proxy->controller_state = NULL;
> + proxy->cs_index_mask = 0x01;
>
> if (chip->swnode) {
> status = device_add_software_node(&proxy->dev, chip-
> >swnode);
> @@ -1024,6 +1029,8 @@ static void spi_set_cs(struct spi_device *spi,
> bool enable, bool force)
> if (!spi->controller->set_cs_timing && !activate)
> spi_delay_exec(&spi->cs_hold, NULL);
>
> + printk("%s() [%d] spi->cs_index_mask == [%d]\n",__func__,
> __LINE__, spi->cs_index_mask);
> +
> if (!(spi->mode & SPI_NO_CS)) {
> /*
> * Historically ACPI has no means of the GPIO polarity and
> @@ -1038,6 +1045,7 @@ static void spi_set_cs(struct spi_device *spi,
> bool enable, bool force)
> for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> if (((spi->cs_index_mask >> idx) & 0x01) &&
> spi_get_csgpiod(spi, idx)) {
> + printk("%s() [%d] idx == [%d]\n",__func__, __LINE__,
> idx);
> if (has_acpi_companion(&spi->dev))
> gpiod_set_value_cansleep(spi_get_csgpiod(spi,
> idx),
> !enable);
> @@ -2514,6 +2522,7 @@ struct spi_device
> *spi_new_ancillary_device(struct spi_device *spi,
> struct spi_controller *ctlr = spi->controller;
> struct spi_device *ancillary;
> int rc = 0;
> + u8 idx;
>
> /* Alloc an spi_device */
> ancillary = spi_alloc_device(ctlr);
> @@ -2524,12 +2533,16 @@ struct spi_device
> *spi_new_ancillary_device(struct spi_device *spi,
>
> strscpy(ancillary->modalias, "dummy", sizeof(ancillary->modalias));
>
> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> + spi_set_chipselect(ancillary, idx, 0xFF);
> +
> /* Use provided chip-select for ancillary device */
> spi_set_chipselect(ancillary, 0, chip_select);
>
> /* Take over SPI mode/speed from SPI main device */
> ancillary->max_speed_hz = spi->max_speed_hz;
> ancillary->mode = spi->mode;
> + ancillary->cs_index_mask = 0x01;
>
> WARN_ON(!mutex_is_locked(&ctlr->add_lock));
>
> @@ -2732,6 +2745,7 @@ struct spi_device *acpi_spi_device_alloc(struct
> spi_controller *ctlr,
> struct acpi_spi_lookup lookup = {};
> struct spi_device *spi;
> int ret;
> + u8 idx;
>
> if (!ctlr && index == -1)
> return ERR_PTR(-EINVAL);
> @@ -2767,12 +2781,16 @@ struct spi_device
> *acpi_spi_device_alloc(struct spi_controller *ctlr,
> return ERR_PTR(-ENOMEM);
> }
>
> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> + spi_set_chipselect(spi, idx, 0xFF);
> +
> ACPI_COMPANION_SET(&spi->dev, adev);
> spi->max_speed_hz = lookup.max_speed_hz;
> spi->mode |= lookup.mode;
> spi->irq = lookup.irq;
> spi->bits_per_word = lookup.bits_per_word;
> spi_set_chipselect(spi, 0, lookup.chip_select);
> + spi->cs_index_mask = 0x01;
>
> return spi;
> }
>
> Regards,
> Amit
>
> >
> > Thanks,
> >
> > Stefan
> >
> > >> Thanks,
> > >>
> > >> Stefan
> > >>
> > >>>> Hi,
> > >>>>
> > >>>> I still see the same error:
> > >>>>
> > >>>> [ 2.748546] pxa2xx-spi pxa2xx-spi.6: chipselect 0 already in use
> > >>> Thank you for the quick testing. For further analysis I have
> > >>> incorporated additional debug prints on top of 1/8 patch. The
> > >>> corresponding diff is shared below. Kindly implement the specified
> > >>> changes, rerun your test and share the kernel logs.
> > >>>
> > >>> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index
> > >>> ff66147ba95f..7f59ea81593d 100644
> > >>> --- a/drivers/spi/spi.c
> > >>> +++ b/drivers/spi/spi.c
> > >>> @@ -618,8 +618,10 @@ static int spi_dev_check(struct device *dev,
> > >>> void
> > >> *data)
> > >>> if (spi->controller == new_spi->controller) {
> > >>> for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>> cs = spi_get_chipselect(spi, idx);
> > >>> + printk("%s() [%d] CS[%d] = [%d]\n",
> > >>> + __func__, __LINE__, idx, cs);
> > >>> for (nw_idx = 0; nw_idx < SPI_CS_CNT_MAX;
> nw_idx++) {
> > >>> - cs_nw = spi_get_chipselect(spi, nw_idx);
> > >>> + cs_nw = spi_get_chipselect(new_spi, nw_idx);
> > >>> + printk("%s() [%d] CS_NEW[%d] =
> > >>> + [%d]\n", __func__, __LINE__, nw_idx, cs_nw);
> > >>> if (cs != 0xFF && cs_nw != 0xFF && cs == cs_nw) {
> > >>> dev_err(dev, "chipselect
> > >>> %d already in use\n",
> > >> cs_nw);
> > >>> return -EBUSY; @@ -659,8
> > >>> +661,10 @@ static int __spi_add_device(struct spi_device *spi)
> > >>> */
> > >>> for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>> cs = spi_get_chipselect(spi, idx);
> > >>> + printk("%s() [%d] CS[%d] = [%d]\n", __func__,
> > >>> + __LINE__, idx, cs);
> > >>> for (nw_idx = idx + 1; nw_idx < SPI_CS_CNT_MAX;
> nw_idx++) {
> > >>> nw_cs = spi_get_chipselect(spi, nw_idx);
> > >>> + printk("%s() [%d] CS_NEW[%d] = [%d]\n",
> > >>> + __func__, __LINE__, nw_idx, nw_cs);
> > >>> if (cs != 0xFF && nw_cs != 0xFF && cs == nw_cs) {
> > >>> dev_err(dev, "chipselect %d already in use\n",
> nw_cs);
> > >>> return -EBUSY; @@ -2401,6 +2405,9
> > >>> @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct
> spi_device
> > *spi,
> > >>> for (idx = 0; idx < rc; idx++)
> > >>> spi_set_chipselect(spi, idx, cs[idx]);
> > >>>
> > >>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > >>> + printk("%s() [%d] CS[%d] = [%d]\n", __func__,
> > >>> + __LINE__, idx, spi_get_chipselect(spi, idx));
> > >>> +
> > >>> /* spi->chip_select[i] gives the corresponding physical CS for
> logical
> > CS i
> > >>> * logical CS number is represented by setting the ith bit
> > >>> in spi- cs_index_mask
> > >>> * So, for example, if spi->cs_index_mask = 0x01 then
> > >>> logical CS number is 0 and
> > >>>
> > >>> Regards,
> > >>> Amit
> > >>>
> > >>>> Thanks,
> > >>>>
> > >>>> Stefan
> > >>>>
> > >>>>>>> + if (cs != 0xFF && cs_nw != 0xFF
> && cs
> > >> ==
> > >>>>>> cs_nw) {
> > >>>>>>> + dev_err(dev, "chipselect
> %d
> > >> already in
> > >>>>>> use\n", cs_nw);
> > >>>>>>> + return -EBUSY;
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>> return 0;
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> @@ -629,13 +640,32 @@ static int __spi_add_device(struct
> > >>>>>>> spi_device
> > >>>> *spi)
> > >>>>>>> {
> > >>>>>>> struct spi_controller *ctlr = spi->controller;
> > >>>>>>> struct device *dev = ctlr->dev.parent;
> > >>>>>>> - int status;
> > >>>>>>> + int status, idx, nw_idx;
> > >>>>>>> + u8 cs, nw_cs;
> > >>>>>>> +
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>>>>>> + /* Chipselects are numbered 0..max; validate. */
> > >>>>>>> + cs = spi_get_chipselect(spi, idx);
> > >>>>>>> + if (cs != 0xFF && cs >= ctlr->num_chipselect) {
> > >>>>>>> + dev_err(dev, "cs%d >= max %d\n",
> > >>>>>> spi_get_chipselect(spi, idx),
> > >>>>>>> + ctlr->num_chipselect);
> > >>>>>>> + return -EINVAL;
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>>
> > >>>>>>> - /* Chipselects are numbered 0..max; validate. */
> > >>>>>>> - if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {
> > >>>>>>> - dev_err(dev, "cs%d >= max %d\n",
> > spi_get_chipselect(spi, 0),
> > >>>>>>> - ctlr->num_chipselect);
> > >>>>>>> - return -EINVAL;
> > >>>>>>> + /*
> > >>>>>>> + * Make sure that multiple logical CS doesn't map to the
> same
> > >>>>>> physical CS.
> > >>>>>>> + * For example, spi->chip_select[0] != spi->chip_select[1]
> and
> > >> so on.
> > >>>>>>> + */
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>>>>>> + cs = spi_get_chipselect(spi, idx);
> > >>>>>>> + for (nw_idx = idx + 1; nw_idx < SPI_CS_CNT_MAX;
> > >> nw_idx++) {
> > >>>>>>> + nw_cs = spi_get_chipselect(spi, nw_idx);
> > >>>>>>> + if (cs != 0xFF && nw_cs != 0xFF && cs ==
> > >> nw_cs) {
> > >>>>>>> + dev_err(dev, "chipselect %d
> already in
> > >> use\n",
> > >>>>>> nw_cs);
> > >>>>>>> + return -EBUSY;
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> /* Set the bus ID string */ @@ -647,11 +677,8 @@ static
> > >>>>>>> int __spi_add_device(struct spi_device
> > >>>> *spi)
> > >>>>>>> * its configuration.
> > >>>>>>> */
> > >>>>>>> status = bus_for_each_dev(&spi_bus_type, NULL, spi,
> > >> spi_dev_check);
> > >>>>>>> - if (status) {
> > >>>>>>> - dev_err(dev, "chipselect %d already in use\n",
> > >>>>>>> - spi_get_chipselect(spi, 0));
> > >>>>>>> + if (status)
> > >>>>>>> return status;
> > >>>>>>> - }
> > >>>>>>>
> > >>>>>>> /* Controller may unregister concurrently */
> > >>>>>>> if (IS_ENABLED(CONFIG_SPI_DYNAMIC) && @@ -659,8
> > >> +686,15 @@
> > >>>>>> static
> > >>>>>>> int __spi_add_device(struct spi_device *spi)
> > >>>>>>> return -ENODEV;
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> - if (ctlr->cs_gpiods)
> > >>>>>>> - spi_set_csgpiod(spi, 0, ctlr-
> > >cs_gpiods[spi_get_chipselect(spi,
> > >>>>>> 0)]);
> > >>>>>>> + if (ctlr->cs_gpiods) {
> > >>>>>>> + u8 cs;
> > >>>>>>> +
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>>>>>> + cs = spi_get_chipselect(spi, idx);
> > >>>>>>> + if (cs != 0xFF)
> > >>>>>>> + spi_set_csgpiod(spi, idx, ctlr-
> > >>> cs_gpiods[cs]);
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>>
> > >>>>>>> /*
> > >>>>>>> * Drivers may modify this initial i/o setup, but will @@
> > >>>>>>> -701,6
> > >>>>>>> +735,9 @@ int spi_add_device(struct spi_device *spi)
> > >>>>>>> struct spi_controller *ctlr = spi->controller;
> > >>>>>>> int status;
> > >>>>>>>
> > >>>>>>> + /* Set the bus ID string */
> > >>>>>>> + spi_dev_set_name(spi);
> > >>>>>>> +
> > >>>>>>> mutex_lock(&ctlr->add_lock);
> > >>>>>>> status = __spi_add_device(spi);
> > >>>>>>> mutex_unlock(&ctlr->add_lock); @@ -942,32 +979,51
> @@
> > >> static
> > >>>>>>> void spi_res_release(struct spi_controller
> > >>>>>> *ctlr, struct spi_message *mes
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>>
> > >>>>>>> /*--------------------------------------------------------------
> > >>>>>>> --
> > >>>>>>> --
> > >>>>>>> --
> > >>>>>>> -----*/
> > >>>>>>> +static inline bool spi_is_last_cs(struct spi_device *spi) {
> > >>>>>>> + u8 idx;
> > >>>>>>> + bool last = false;
> > >>>>>>> +
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>>>>>> + if ((spi->cs_index_mask >> idx) & 0x01) {
> > >>>>>>> + if (spi->controller->last_cs[idx] ==
> > >>>>>> spi_get_chipselect(spi, idx))
> > >>>>>>> + last = true;
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>> + return last;
> > >>>>>>> +}
> > >>>>>>> +
> > >>>>>>>
> > >>>>>>> static void spi_set_cs(struct spi_device *spi, bool enable,
> bool
> > force)
> > >>>>>>> {
> > >>>>>>> bool activate = enable;
> > >>>>>>> + u8 idx;
> > >>>>>>>
> > >>>>>>> /*
> > >>>>>>> * Avoid calling into the driver (or doing delays) if the
> > >>>>>>> chip
> > >> select
> > >>>>>>> * isn't actually changing from the last time this was
> called.
> > >>>>>>> */
> > >>>>>>> - if (!force && ((enable && spi->controller->last_cs ==
> > >>>>>> spi_get_chipselect(spi, 0)) ||
> > >>>>>>> - (!enable && spi->controller->last_cs !=
> > >>>>>> spi_get_chipselect(spi, 0))) &&
> > >>>>>>> + if (!force && ((enable && spi->controller-
> >last_cs_index_mask
> > >> ==
> > >>>>>>> +spi-
> > >>>>>>> cs_index_mask &&
> > >>>>>>> + spi_is_last_cs(spi)) ||
> > >>>>>>> + (!enable && spi->controller-
> >last_cs_index_mask
> > >> == spi-
> > >>>>>>> cs_index_mask &&
> > >>>>>>> + !spi_is_last_cs(spi))) &&
> > >>>>>>> (spi->controller->last_cs_mode_high == (spi->mode &
> > >>>>>> SPI_CS_HIGH)))
> > >>>>>>> return;
> > >>>>>>>
> > >>>>>>> trace_spi_set_cs(spi, activate);
> > >>>>>>>
> > >>>>>>> - spi->controller->last_cs = enable ? spi_get_chipselect(spi,
> 0) : -
> > 1;
> > >>>>>>> + spi->controller->last_cs_index_mask = spi-
> >cs_index_mask;
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > >>>>>>> + spi->controller->last_cs[idx] = enable ?
> > >>>>>>> +spi_get_chipselect(spi,
> > >>>>>> 0)
> > >>>>>>> +: -1;
> > >>>>>>> spi->controller->last_cs_mode_high = spi->mode &
> > >> SPI_CS_HIGH;
> > >>>>>>> - if ((spi_get_csgpiod(spi, 0) || !spi->controller-
> >set_cs_timing)
> > &&
> > >>>>>> !activate)
> > >>>>>>> - spi_delay_exec(&spi->cs_hold, NULL);
> > >>>>>>> -
> > >>>>>>> if (spi->mode & SPI_CS_HIGH)
> > >>>>>>> enable = !enable;
> > >>>>>>>
> > >>>>>>> - if (spi_get_csgpiod(spi, 0)) {
> > >>>>>>> + if (spi_is_csgpiod(spi)) {
> > >>>>>>> + if (!spi->controller->set_cs_timing && !activate)
> > >>>>>>> + spi_delay_exec(&spi->cs_hold, NULL);
> > >>>>>>> +
> > >>>>>>> if (!(spi->mode & SPI_NO_CS)) {
> > >>>>>>> /*
> > >>>>>>> * Historically ACPI has no means of the
> GPIO
> > >> polarity
> > >>>>>> and @@
> > >>>>>>> -979,26 +1035,38 @@ static void spi_set_cs(struct spi_device
> > >>>>>>> *spi, bool
> > >>>>>> enable, bool force)
> > >>>>>>> * ambiguity. That's why we use enable,
> that
> > >> takes
> > >>>>>> SPI_CS_HIGH
> > >>>>>>> * into account.
> > >>>>>>> */
> > >>>>>>> - if (has_acpi_companion(&spi->dev))
> > >>>>>>> -
> > >>>>>> gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0),
> !enable);
> > >>>>>>> - else
> > >>>>>>> - /* Polarity handled by GPIO
> library */
> > >>>>>>> -
> > >>>>>> gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0),
> activate);
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX;
> idx++) {
> > >>>>>>> + if (((spi->cs_index_mask >> idx)
> &
> > >> 0x01) &&
> > >>>>>>> + spi_get_csgpiod(spi, idx)) {
> > >>>>>>> + if
> (has_acpi_companion(&spi-
> > >>> dev))
> > >>>>>>> +
> > >>>>>> gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx),
> > >>>>>>> +
> > >>>>>> !enable);
> > >>>>>>> + else
> > >>>>>>> + /* Polarity
> handled by
> > >> GPIO
> > >>>>>> library */
> > >>>>>>> +
> > >>>>>> gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx),
> > >>>>>>> +
> > >>>>>> activate);
> > >>>>>>> +
> > >>>>>>> + if (activate)
> > >>>>>>> +
> spi_delay_exec(&spi-
> > >>>>>>> cs_setup, NULL);
> > >>>>>>> + else
> > >>>>>>> +
> spi_delay_exec(&spi-
> > >>>>>>> cs_inactive, NULL);
> > >>>>>>> + }
> > >>>>>>> + }
> > >>>>>>> }
> > >>>>>>> /* Some SPI masters need both GPIO CS &
> > >> slave_select */
> > >>>>>>> if ((spi->controller->flags &
> > >> SPI_CONTROLLER_GPIO_SS) &&
> > >>>>>>> spi->controller->set_cs)
> > >>>>>>> spi->controller->set_cs(spi, !enable);
> > >>>>>>> +
> > >>>>>>> + if (!spi->controller->set_cs_timing) {
> > >>>>>>> + if (activate)
> > >>>>>>> + spi_delay_exec(&spi->cs_setup,
> > >> NULL);
> > >>>>>>> + else
> > >>>>>>> + spi_delay_exec(&spi-
> >cs_inactive,
> > >> NULL);
> > >>>>>>> + }
> > >>>>>>> } else if (spi->controller->set_cs) {
> > >>>>>>> spi->controller->set_cs(spi, !enable);
> > >>>>>>> }
> > >>>>>>> -
> > >>>>>>> - if (spi_get_csgpiod(spi, 0) || !spi->controller-
> >set_cs_timing) {
> > >>>>>>> - if (activate)
> > >>>>>>> - spi_delay_exec(&spi->cs_setup, NULL);
> > >>>>>>> - else
> > >>>>>>> - spi_delay_exec(&spi->cs_inactive, NULL);
> > >>>>>>> - }
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> #ifdef CONFIG_HAS_DMA
> > >>>>>>> @@ -2222,8 +2290,8 @@ static void
> > >>>>>>> of_spi_parse_dt_cs_delay(struct
> > >>>>>> device_node *nc,
> > >>>>>>> static int of_spi_parse_dt(struct spi_controller *ctlr,
> > >>>>>>> struct spi_device
> > >>>> *spi,
> > >>>>>>> struct device_node *nc)
> > >>>>>>> {
> > >>>>>>> - u32 value;
> > >>>>>>> - int rc;
> > >>>>>>> + u32 value, cs[SPI_CS_CNT_MAX];
> > >>>>>>> + int rc, idx;
> > >>>>>>>
> > >>>>>>> /* Mode (clock phase/polarity/etc.) */
> > >>>>>>> if (of_property_read_bool(nc, "spi-cpha")) @@ -2295,14
> > >>>>>>> +2363,52
> > >>>>>> @@
> > >>>>>>> static int of_spi_parse_dt(struct spi_controller *ctlr, struct
> > >>>>>>> spi_device
> > >> *spi,
> > >>>>>>> return 0;
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> + if (ctlr->num_chipselect > SPI_CS_CNT_MAX) {
> > >>>>>>> + dev_err(&ctlr->dev, "No. of CS is more than max.
> no.
> > >> of
> > >>>>>> supported CS\n");
> > >>>>>>> + return -EINVAL;
> > >>>>>>> + }
> > >>>>>>> +
> > >>>>>>> + /*
> > >>>>>>> + * Zero(0) is a valid physical CS value and can be located at
> > >> any
> > >>>>>>> + * logical CS in the spi->chip_select[]. If all the physical CS
> > >>>>>>> + * are initialized to 0 then It would be difficult to
> differentiate
> > >>>>>>> + * between a valid physical CS 0 & an unused logical CS
> whose
> > >>>>>> physical
> > >>>>>>> + * CS can be 0. As a solution to this issue initialize all the
> > >>>>>>> +CS to
> > >> 0xFF.
> > >>>>>>> + * Now all the unused logical CS will have 0xFF physical CS
> > >>>>>>> +value & can
> > >>>>>> be
> > >>>>>>> + * ignore while performing physical CS validity checks.
> > >>>>>>> + */
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > >>>>>>> + spi_set_chipselect(spi, idx, 0xFF);
> > >>>>>>> +
> > >>>>>>> /* Device address */
> > >>>>>>> - rc = of_property_read_u32(nc, "reg", &value);
> > >>>>>>> - if (rc) {
> > >>>>>>> + rc = of_property_read_variable_u32_array(nc, "reg",
> &cs[0],
> > >> 1,
> > >>>>>>> +
> SPI_CS_CNT_MAX);
> > >>>>>>> + if (rc < 0) {
> > >>>>>>> dev_err(&ctlr->dev, "%pOF has no valid 'reg'
> property
> > >>>>>> (%d)\n",
> > >>>>>>> nc, rc);
> > >>>>>>> return rc;
> > >>>>>>> }
> > >>>>>>> - spi_set_chipselect(spi, 0, value);
> > >>>>>>> + if (rc > ctlr->num_chipselect) {
> > >>>>>>> + dev_err(&ctlr->dev, "%pOF has number of CS >
> ctlr-
> > >>>>>>> num_chipselect (%d)\n",
> > >>>>>>> + nc, rc);
> > >>>>>>> + return rc;
> > >>>>>>> + }
> > >>>>>>> + if ((of_property_read_bool(nc, "parallel-memories")) &&
> > >>>>>>> + (!(ctlr->flags & SPI_CONTROLLER_MULTI_CS))) {
> > >>>>>>> + dev_err(&ctlr->dev, "SPI controller doesn't
> support
> > >> multi
> > >>>>>> CS\n");
> > >>>>>>> + return -EINVAL;
> > >>>>>>> + }
> > >>>>>>> + for (idx = 0; idx < rc; idx++)
> > >>>>>>> + spi_set_chipselect(spi, idx, cs[idx]);
> > >>>>>>> +
> > >>>>>>> + /* spi->chip_select[i] gives the corresponding physical CS
> for
> > >>>>>>> +logical CS
> > >>>>>> i
> > >>>>>>> + * logical CS number is represented by setting the ith bit in
> > >>>>>>> +spi-
> > >>>>>>> cs_index_mask
> > >>>>>>> + * So, for example, if spi->cs_index_mask = 0x01 then
> logical
> > >> CS
> > >>>>>> number is 0 and
> > >>>>>>> + * spi->chip_select[0] will give the physical CS.
> > >>>>>>> + * By default spi->chip_select[0] will hold the physical CS
> > >>>>>>> +number so,
> > >>>>>> set
> > >>>>>>> + * spi->cs_index_mask as 0x01.
> > >>>>>>> + */
> > >>>>>>> + spi->cs_index_mask = 0x01;
> > >>>>>>>
> > >>>>>>> /* Device speed */
> > >>>>>>> if (!of_property_read_u32(nc, "spi-max-frequency",
> > >>>>>>> &value)) @@
> > >>>>>>> -3100,6 +3206,7 @@ int spi_register_controller(struct
> > >>>>>>> spi_controller
> > >> *ctlr)
> > >>>>>>> struct boardinfo *bi;
> > >>>>>>> int first_dynamic;
> > >>>>>>> int status;
> > >>>>>>> + int idx;
> > >>>>>>>
> > >>>>>>> if (!dev)
> > >>>>>>> return -ENODEV;
> > >>>>>>> @@ -3164,7 +3271,8 @@ int spi_register_controller(struct
> > >>>>>>> spi_controller
> > >>>>>> *ctlr)
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> /* Setting last_cs to -1 means no chip selected */
> > >>>>>>> - ctlr->last_cs = -1;
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
> > >>>>>>> + ctlr->last_cs[idx] = -1;
> > >>>>>>>
> > >>>>>>> status = device_add(&ctlr->dev);
> > >>>>>>> if (status < 0)
> > >>>>>>> @@ -3889,7 +3997,7 @@ static int __spi_validate(struct
> > >>>>>>> spi_device *spi,
> > >>>>>> struct spi_message *message)
> > >>>>>>> * cs_change is set for each transfer.
> > >>>>>>> */
> > >>>>>>> if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits &
> > >>>>>> SPI_CS_WORD) ||
> > >>>>>>> - spi_get_csgpiod(spi, 0)))
> {
> > >>>>>>> + spi_is_csgpiod(spi))) {
> > >>>>>>> size_t maxsize = BITS_TO_BYTES(spi-
> >bits_per_word);
> > >>>>>>> int ret;
> > >>>>>>>
> > >>>>>>> diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
> > >>>>>>> index 7b4baff63c5c..871d3a6d879b 100644
> > >>>>>>> --- a/include/linux/spi/spi.h
> > >>>>>>> +++ b/include/linux/spi/spi.h
> > >>>>>>> @@ -20,6 +20,9 @@
> > >>>>>>>
> > >>>>>>> #include <uapi/linux/spi/spi.h>
> > >>>>>>>
> > >>>>>>> +/* Max no. of CS supported per spi device */ #define
> > >>>>>>> +SPI_CS_CNT_MAX
> > >>>>>>> +4
> > >>>>>>> +
> > >>>>>>> struct dma_chan;
> > >>>>>>> struct software_node;
> > >>>>>>> struct ptp_system_timestamp; @@ -132,7 +135,8 @@
> extern
> > >>>>>>> void
> > >>>>>> spi_transfer_cs_change_delay_exec(struct spi_message *msg,
> > >>>>>>> * @max_speed_hz: Maximum clock rate to be used with this
> chip
> > >>>>>>> * (on this board); may be changed by the device's driver.
> > >>>>>>> * The spi_transfer.speed_hz can override this for each
> transfer.
> > >>>>>>> - * @chip_select: Chipselect, distinguishing chips handled by
> > >> @controller.
> > >>>>>>> + * @chip_select: Array of physical chipselect, spi->chipselect[i]
> gives
> > >>>>>>> + * the corresponding physical CS for logical CS i.
> > >>>>>>> * @mode: The spi mode defines how data is clocked out and
> in.
> > >>>>>>> * This may be changed by the device's driver.
> > >>>>>>> * The "active low" default for chipselect mode can be
> > >> overridden
> > >>>>>>> @@ -157,8 +161,8 @@ extern void
> > >>>>>> spi_transfer_cs_change_delay_exec(struct spi_message *msg,
> > >>>>>>> * the device will bind to the named driver and only the
> named
> > >> driver.
> > >>>>>>> * Do not set directly, because core frees it; use
> > >> driver_set_override() to
> > >>>>>>> * set or clear it.
> > >>>>>>> - * @cs_gpiod: GPIO descriptor of the chipselect line (optional,
> > >>>>>>> NULL
> > >>>> when
> > >>>>>>> - * not using a GPIO line)
> > >>>>>>> + * @cs_gpiod: Array of GPIO descriptors of the corresponding
> > >>>>>>> + chipselect
> > >>>>>> lines
> > >>>>>>> + * (optional, NULL when not using a GPIO line)
> > >>>>>>> * @word_delay: delay to be inserted between consecutive
> > >>>>>>> * words of a transfer
> > >>>>>>> * @cs_setup: delay to be introduced by the controller
> > >>>>>>> after CS is asserted @@ -167,6 +171,7 @@ extern void
> > >>>>>> spi_transfer_cs_change_delay_exec(struct spi_message *msg,
> > >>>>>>> * deasserted. If @cs_change_delay is used from
> @spi_transfer,
> > >> then
> > >>>>>> the
> > >>>>>>> * two delays will be added up.
> > >>>>>>> * @pcpu_statistics: statistics for the spi_device
> > >>>>>>> + * @cs_index_mask: Bit mask of the active chipselect(s) in the
> > >>>>>>> + chipselect array
> > >>>>>>> *
> > >>>>>>> * A @spi_device is used to interchange data between an SPI
> slave
> > >>>>>>> * (usually a discrete chip) and CPU memory.
> > >>>>>>> @@ -182,7 +187,7 @@ struct spi_device {
> > >>>>>>> struct spi_controller *controller;
> > >>>>>>> struct spi_controller *master; /* Compatibility
> layer
> > >> */
> > >>>>>>> u32 max_speed_hz;
> > >>>>>>> - u8 chip_select;
> > >>>>>>> + u8 chip_select[SPI_CS_CNT_MAX];
> > >>>>>>> u8 bits_per_word;
> > >>>>>>> bool rt;
> > >>>>>>> #define SPI_NO_TX BIT(31) /* No
> transmit wire */
> > >>>>>>> @@ -213,7 +218,7 @@ struct spi_device {
> > >>>>>>> void *controller_data;
> > >>>>>>> char modalias[SPI_NAME_SIZE];
> > >>>>>>> const char *driver_override;
> > >>>>>>> - struct gpio_desc *cs_gpiod; /* Chip select GPIO
> > descriptor
> > >>>>>> */
> > >>>>>>> + struct gpio_desc *cs_gpiod[SPI_CS_CNT_MAX]; /*
> > >> Chip select
> > >>>>>> gpio desc */
> > >>>>>>> struct spi_delay word_delay; /* Inter-word delay */
> > >>>>>>> /* CS delays */
> > >>>>>>> struct spi_delay cs_setup;
> > >>>>>>> @@ -223,6 +228,13 @@ struct spi_device {
> > >>>>>>> /* The statistics */
> > >>>>>>> struct spi_statistics __percpu *pcpu_statistics;
> > >>>>>>>
> > >>>>>>> + /* Bit mask of the chipselect(s) that the driver need to use
> > >> from
> > >>>>>>> + * the chipselect array.When the controller is capable to
> > >> handle
> > >>>>>>> + * multiple chip selects & memories are connected in
> parallel
> > >>>>>>> + * then more than one bit need to be set in
> cs_index_mask.
> > >>>>>>> + */
> > >>>>>>> + u32 cs_index_mask :
> SPI_CS_CNT_MAX;
> > >>>>>>> +
> > >>>>>>> /*
> > >>>>>>> * Likely need more hooks for more protocol options
> > >>>>>>> affecting
> > >> how
> > >>>>>>> * the controller talks to each chip, like:
> > >>>>>>> @@ -279,22 +291,33 @@ static inline void
> *spi_get_drvdata(const
> > >>>>>>> struct spi_device *spi)
> > >>>>>>>
> > >>>>>>> static inline u8 spi_get_chipselect(const struct spi_device
> *spi, u8
> > idx)
> > >>>>>>> {
> > >>>>>>> - return spi->chip_select;
> > >>>>>>> + return spi->chip_select[idx];
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> static inline void spi_set_chipselect(struct spi_device
> > >>>>>>> *spi,
> > >>>>>>> u8 idx, u8
> > >>>>>> chipselect)
> > >>>>>>> {
> > >>>>>>> - spi->chip_select = chipselect;
> > >>>>>>> + spi->chip_select[idx] = chipselect;
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> static inline struct gpio_desc *spi_get_csgpiod(const
> > >>>>>>> struct spi_device *spi,
> > >>>>>> u8 idx)
> > >>>>>>> {
> > >>>>>>> - return spi->cs_gpiod;
> > >>>>>>> + return spi->cs_gpiod[idx];
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> static inline void spi_set_csgpiod(struct spi_device *spi,
> > >>>>>>> u8 idx, struct
> > >>>>>> gpio_desc *csgpiod)
> > >>>>>>> {
> > >>>>>>> - spi->cs_gpiod = csgpiod;
> > >>>>>>> + spi->cs_gpiod[idx] = csgpiod;
> > >>>>>>> +}
> > >>>>>>> +
> > >>>>>>> +static inline bool spi_is_csgpiod(struct spi_device *spi) {
> > >>>>>>> + u8 idx;
> > >>>>>>> +
> > >>>>>>> + for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
> > >>>>>>> + if (spi_get_csgpiod(spi, idx))
> > >>>>>>> + return true;
> > >>>>>>> + }
> > >>>>>>> + return false;
> > >>>>>>> }
> > >>>>>>>
> > >>>>>>> /**
> > >>>>>>> @@ -399,6 +422,8 @@ extern struct spi_device
> > >>>>>> *spi_new_ancillary_device(struct spi_device *spi, u8 ch
> > >>>>>>> * @bus_lock_spinlock: spinlock for SPI bus locking
> > >>>>>>> * @bus_lock_mutex: mutex for exclusion of multiple callers
> > >>>>>>> * @bus_lock_flag: indicates that the SPI bus is locked for
> > >>>>>>> exclusive use
> > >>>>>>> + * @multi_cs_cap: indicates that the SPI Controller can
> > >>>>>>> + assert/de-
> > >> assert
> > >>>>>>> + * more than one chip select at once.
> > >>>>>>> * @setup: updates the device mode and clocking records
> used by
> > a
> > >>>>>>> * device's SPI controller; protocol code may call this. This
> > >>>>>>> * must fail if an unrecognized or unsupported mode is
> > >> requested.
> > >>>>>>> @@ -567,6 +592,11 @@ struct spi_controller {
> > >>>>>>> #define SPI_CONTROLLER_MUST_TX BIT(4)
> /*
> > Requires tx
> > >>>> */
> > >>>>>>> #define SPI_CONTROLLER_GPIO_SS BIT(5)
> /* GPIO CS
> > >>>> must
> > >>>>>> select slave */
> > >>>>>>> #define SPI_CONTROLLER_SUSPENDED BIT(6) /*
> Currently
> > >>>>>> suspended */
> > >>>>>>> + /*
> > >>>>>>> + * The spi-controller has multi chip select capability and
> can
> > >>>>>>> + * assert/de-assert more than one chip select at once.
> > >>>>>>> + */
> > >>>>>>> +#define SPI_CONTROLLER_MULTI_CS BIT(7)
> > >>>>>>>
> > >>>>>>> /* Flag indicating if the allocation of this struct is
> > >>>>>>> devres-
> > >> managed */
> > >>>>>>> bool devm_allocated;
> > >>>>>>> @@ -677,7 +707,8 @@ struct spi_controller {
> > >>>>>>> bool rt;
> > >>>>>>> bool auto_runtime_pm;
> > >>>>>>> bool cur_msg_mapped;
> > >>>>>>> - char last_cs;
> > >>>>>>> + char
> last_cs[SPI_CS_CNT_MAX];
> > >>>>>>> + char last_cs_index_mask;
> > >>>>>>> bool last_cs_mode_high;
> > >>>>>>> bool fallback;
> > >>>>>>> struct completion xfer_completion;
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