Re: [MeeGo-Dev][PATCH] Topcliff: Update PCH_SPI driver to 2.6.35

From: Masayuki Ohtake
Date: Tue Aug 31 2010 - 08:09:48 EST


----- Original Message -----
From: "Grant Likely" <grant.likely@xxxxxxxxxxxx>
To: "Masayuki Ohtak" <masa-korg@xxxxxxxxxxxxxxx>
Cc: <meego-dev@xxxxxxxxx>; "LKML" <linux-kernel@xxxxxxxxxxxxxxx>; "David Brownell" <dbrownell@xxxxxxxxxxxxxxxxxxxxx>;
<qi.wang@xxxxxxxxx>; <yong.y.wang@xxxxxxxxx>; <andrew.chih.howe.khor@xxxxxxxxx>; <arjan@xxxxxxxxxxxxxxx>;
<gregkh@xxxxxxx>; "Tomoya MORINAGA" <morinaga526@xxxxxxxxxxxxxxx>; "Thomas Gleixner" <tglx@xxxxxxxxxxxxx>; "David
Woodhouse" <dwmw2@xxxxxxxxxxxxx>
Sent: Saturday, August 28, 2010 3:33 AM
Subject: Re: [MeeGo-Dev][PATCH] Topcliff: Update PCH_SPI driver to 2.6.35


> [cc'ing Thomas Gleixner and David Woodhouse since this driver needs to
> get some data about the platform (to know what spi_devices are
> present) and I don't know how that is handled for x86 SoCs.]
>
> Hi Ohtak-san,
>
> Comments below.
>
> 2010/8/27 Masayuki Ohtak <masa-korg@xxxxxxxxxxxxxxx>:
> > Hi Grant and Linus Walleij
> >
> > I have modified your indications.
> > Please check below.
> > ---
> >
> > SPI driver of Topcliff PCH
> >
> > Topcliff PCH is the platform controller hub that is going to be used in
> > Intel's upcoming general embedded platform. All IO peripherals in
> > Topcliff PCH are actually devices sitting on AMBA bus.
> > Topcliff PCH has SPI I/F. Using this I/F, it is able to access system
> > devices connected to SPI.
> >
> > Signed-off-by: Masayuki Ohtake <masa-korg@xxxxxxxxxxxxxxx>
> > ---
> > drivers/spi/Kconfig | 27 +
> > drivers/spi/Makefile | 3 +
> > drivers/spi/spi_pch.c | 1686
> > ++++++++++++++++++++++++++++++++++++++++++
> > drivers/spi/spi_pch.h | 179 +++++
> > drivers/spi/spi_pch_device.c | 56 ++
> > 5 files changed, 1951 insertions(+), 0 deletions(-)
> > create mode 100644 drivers/spi/spi_pch.c
> > create mode 100644 drivers/spi/spi_pch.h
> > create mode 100644 drivers/spi/spi_pch_device.c
> >
> > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> > index 91c2f4f..ff048b2 100644
> > --- a/drivers/spi/Kconfig
> > +++ b/drivers/spi/Kconfig
> > @@ -53,6 +53,33 @@ if SPI_MASTER
> >
> > comment "SPI Master Controller Drivers"
> >
> > +config PCH_SPI
> > + tristate "PCH SPI Controller"
> > + depends on PCI
> > + help
> > + This driver is for PCH(Platform controller Hub) SPI of Topcliff which
> > + is an IOH(Input/Output Hub) for x86 embedded processor.
> > + This driver can access PCH SPI bus device.
> > +
> > +config PCH_SPI_PLATFORM_DEVICE
> > + boolean
> > + depends on PCH_SPI
> > + default y if PCH_SPI
> > + help
> > + This driver is for PCH SPI of Topcliff which is an
> > + IOH(Input/Output Hub) for x86 embedded processor.
> > + This registers SPI devices for a given board.
>
> This shouldn't be a separate driver. The SoC platform setup code
> should take care of registering the devices which will be on the spi
> bus which can be done before the bus device is initialized.

I will modify to a single file.

>
> > +
> > +config PCH_SPI_PLATFORM_DEVICE_COUNT
> > + int "PCH SPI Bus count"
> > + range 1 2
> > + depends on PCH_SPI_PLATFORM_DEVICE
> > + help
> > + This driver is for PCH(Platform controller Hub) SPI of Topcliff which
> > + is an IOH(Input/Output Hub) for x86 embedded processor.
> > + The number of SPI buses/channels supported by the PCH SPI controller.
> > + PCH SPI of Topcliff supports only one channel.
>
> Hmmm. I think I misunderstood the purpose of this symbol in your
> initial posting. This isn't the number of busses (as I originally
> thought), but the number of devices registered on the bus. I should
> have read more carefully. As mentioned above, this shouldn't be
> specified in the kernel config or as a separate driver, but I don't
> know how you should specify it for x86 SoCs. I've cc'd Thomas and
> David so that they can provide their feedback.
>
> > +
> > config SPI_ATMEL
> > tristate "Atmel SPI Controller"
> > depends on (ARCH_AT91 || AVR32)
> > diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> > index e9cbd18..b07fb5b 100644
> > --- a/drivers/spi/Makefile
> > +++ b/drivers/spi/Makefile
> > @@ -64,3 +64,6 @@ obj-$(CONFIG_SPI_TLE62X0) += tle62x0.o
> >
> > # SPI slave drivers (protocol for that link)
> > # ... add above this line ...
> > +obj-$(CONFIG_PCH_SPI_PLATFORM_DEVICE) += spi_pch_device.o
> > +obj-$(CONFIG_PCH_SPI) += spi_pch.o
> > +
> > diff --git a/drivers/spi/spi_pch.c b/drivers/spi/spi_pch.c
> > new file mode 100644
> > index 0000000..4124238
> > --- /dev/null
> > +++ b/drivers/spi/spi_pch.c
> > @@ -0,0 +1,1686 @@
> > +/*
>
> Still need to add a one-line summary of what this file is for. Something like:
>
> /*
> * SPI bus driver for the Intel Topcliff SoC
>
> > + * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; version 2 of the License.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > + * GNU General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License
> > + * along with this program; if not, write to the Free Software
> > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307,
> > USA.
> > + */
> > +
> > +#include <linux/pci.h>
> > +#include <linux/wait.h>
> > +#include <linux/spi/spi.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/sched.h>
> > +#include <linux/spi/spidev.h>
> > +#include <linux/module.h>
> > +#include <linux/device.h>
> > +#include <linux/mutex.h>
> > +#include "spi_pch.h"
> > +
> > +static struct pci_device_id pch_spi_pcidev_id[] = {
> > + {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_GE_SPI)},
> > + {0,}
> > +};
> > +
> > +static DEFINE_MUTEX(pch_spi_mutex);
>
> Move into private data structure.
>
> > +
> > +/**
> > + * pch_spi_writereg() - Performs register writes
> > + * @master: Pointer to struct spi_master.
> > + * @idx: Register offset.
> > + * @val: Value to be written to register.
> > + */
> > +static inline void pch_spi_writereg(struct spi_master *master, int idx, u32
> > val)
> > +{
> > +
> > + struct pch_spi_data *data = spi_master_get_devdata(master);
> > +
> > + iowrite32(val, (data->io_remap_addr + idx));
> > +
> > + dev_dbg(&master->dev, "%s Offset=%x Value=%x\n", __func__, idx, val);
> > +}
> > +
> > +/**
> > + * pch_spi_readreg() - Performs register reads
> > + * @master: Pointer to struct spi_master.
> > + * @idx: Register offset.
> > + */
> > +static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
> > +{
> > + u32 reg_data;
> > +
> > + struct pch_spi_data *data = spi_master_get_devdata(master);
> > +
> > + dev_dbg(&master->dev, "%s Offset=%x\n", __func__, idx);
> > + reg_data = ioread32((data->io_remap_addr + idx));
> > +
> > + dev_dbg(&master->dev, "%s Content=%x\n", __func__, reg_data);
> > + return reg_data;
> > +}
> > +
> > +static void pch_spi_set_master_mode(struct spi_master *master)
> > +{
> > + u32 reg_spcr_val;
> > + reg_spcr_val = pch_spi_readreg(master, PCH_SPCR);
> > + dev_dbg(&master->dev, "%s SPCR content=%x\n", __func__, reg_spcr_val);
> > +
> > + /* sets the second bit of SPCR to 1:master mode */
> > + PCH_SET_BITMSK(reg_spcr_val, SPCR_MSTR_BIT);
> > +
> > + /* write the value to SPCR register */
> > + pch_spi_writereg(master, PCH_SPCR, reg_spcr_val);
> > + dev_dbg(&master->dev, "%s SPCR after setting MSTR bit=%x\n",
> > + __func__, reg_spcr_val);
> > +}
> > +
> > +/**
> > + * ch_spi_disable_interrupts() - Disables specified interrupts
> > + * @master: Pointer to struct spi_master.
> > + * @interrupt: Interrups to be enabled.
> > + */
> > +static void pch_spi_disable_interrupts(struct spi_master *master, u8
> > interrupt)
> > +{
> > + u32 reg_val_spcr;
> > +
> > + reg_val_spcr = pch_spi_readreg(master, PCH_SPCR);
> > +
> > + dev_dbg(&master->dev, "%s SPCR content =%x\n",
> > + __func__, reg_val_spcr);
> > +
> > + if (interrupt & PCH_RFI) {
> > + /* clear RFIE bit in SPCR */
> > + dev_dbg(&master->dev,
> > + "%s clearing RFI in pch_spi_disable_interrupts\n",
> > + __func__);
> > + PCH_CLR_BITMSK(reg_val_spcr, SPCR_RFIE_BIT);
> > + }
> > +
> > + if (interrupt & PCH_TFI) {
> > + /* clear TFIE bit in SPCR */
> > + dev_dbg(&master->dev,
> > + "%s clearing TFI in pch_spi_disable_interrupts\n",
> > + __func__);
> > + PCH_CLR_BITMSK(reg_val_spcr, SPCR_TFIE_BIT);
> > + }
> > +
> > + if (interrupt & PCH_FI) {
> > + /* clear FIE bit in SPCR */
> > + dev_dbg(&master->dev,
> > + "%s clearing FI in pch_spi_disable_interrupts\n",
> > + __func__);
> > + PCH_CLR_BITMSK(reg_val_spcr, SPCR_FIE_BIT);
> > + }
> > +
> > + if (interrupt & PCH_ORI) {
> > + /* clear ORIE bit in SPCR */
> > + dev_dbg(&master->dev,
> > + "%s clearing ORI in pch_spi_disable_interrupts\n",
> > + __func__);
> > + PCH_CLR_BITMSK(reg_val_spcr, SPCR_ORIE_BIT);
> > + }
> > +
> > + if (interrupt & PCH_MDFI) {
> > + /* clear MODFIE bit in SPCR */
> > + dev_dbg(&master->dev,
> > + "%s clearing MDFI in pch_spi_disable_interrupts\n",
> > + __func__);
> > + PCH_CLR_BITMSK(reg_val_spcr, SPCR_MDFIE_BIT);
> > + }
> > +
> > + pch_spi_writereg(master, PCH_SPCR, reg_val_spcr);
>
> This seems overly verbose. Can this function simply do:
>
> reg_val_spcr = pch_spi_readreg(master, PCH_SPCR);
> reg_val_spcr &= ~(interrupts);
> pch_spi_writereg(master, PCH_SPCR, reg_val_spcr);
>
>

It seems the above your code is not qual to our original code.


> > +
> > + dev_dbg(&master->dev, "%s SPCR after disabling interrupts =%x\n",
> > + __func__, reg_val_spcr);
> > +}
> > +
> > +/**
> > + * pch_spi_set_enable() - Sets/Resets the SPE bit in SPCR
> > + * @spi: Pointer to struct spi_device.
> > + * @enable: To enable/disable SPI transfer enable.
> > + * One can provide multiple line descriptions
> > + * for arguments.
> > + */
> > +static void pch_spi_set_enable(const struct spi_device *spi, u8 enable)
>
> Use 'bool' instead of 'u8' for enable.
>
> > +{
> > + u32 reg_spcr_val;
> > +
> > + reg_spcr_val = pch_spi_readreg(spi->master, PCH_SPCR);
> > + dev_dbg(&spi->dev, "%s SPCR content=%x\n", __func__, reg_spcr_val);
> > +
> > + if (enable == true) {
> > + dev_dbg(&spi->dev, "%s enable==true\n", __func__);
> > + PCH_SET_BITMSK(reg_spcr_val, SPCR_SPE_BIT);
> > + } else {
> > + dev_dbg(&spi->dev, "%s enable==false\n", __func__);
> > + PCH_CLR_BITMSK(reg_spcr_val, SPCR_SPE_BIT);
> > + }
> > +
> > + pch_spi_writereg(spi->master, PCH_SPCR, reg_spcr_val);
> > +
> > + dev_dbg(&spi->dev, "%s SPCR content after modifying SPE=%x\n",
> > + __func__, reg_spcr_val);
> > +}
>
> This function is only used twice; once to enable and once to disable.
> The driver would be clearer if it was simply open coded at callsite.
>
> > +
> > +static void pch_spi_callback(struct pch_spi_data *data)
> > +{
> > + dev_dbg(&data->master->dev, "%s waking up process\n", __func__);
> > + spin_lock(&data->lock);
> > + data->transfer_complete = true;
> > + wake_up(&data->wait);
> > + dev_dbg(&data->master->dev, "%s invoked wake_up\n", __func__);
> > + spin_unlock(&data->lock);
> > +}
>
> Also only called in one place; should be open-coded at call site.
>
> > +static void pch_spi_handler_sub(struct pch_spi_data *data, u32
> > reg_spsr_val,
> > + void __iomem *io_remap_addr)
> > +{
> > + /* book keeping variables */
> > + u32 n_read, tx_index, rx_index, bpw_len;
> > +
> > + /* buffer to store rx/tx data */
> > + u16 *pkt_rx_buffer, *pkt_tx_buff;
> > +
> > + /* read/write indices */
> > + int read_cnt;
> > +
> > + /* SPSR content */
> > + u32 reg_spcr_val;
> > +
> > + /* register addresses */
> > + void __iomem *spsr;
> > + void __iomem *spdrr;
> > + void __iomem *spdwr;
> > +
> > + spsr = io_remap_addr + PCH_SPSR;
> > + iowrite32(reg_spsr_val, spsr);
> > +
> > + if (data->transfer_active == true) {
> > + rx_index = data->rx_index;
> > + tx_index = data->tx_index;
> > + bpw_len = data->bpw_len;
> > + pkt_rx_buffer = data->pkt_rx_buff;
> > + pkt_tx_buff = data->pkt_tx_buff;
> > +
> > + spdrr = io_remap_addr + PCH_SPDRR;
> > + spdwr = io_remap_addr + PCH_SPDWR;
> > +
> > + n_read = PCH_READABLE(reg_spsr_val);
> > +
> > + for (read_cnt = 0; (read_cnt < n_read);
> > + read_cnt++) {
> > + /* read data */
> > + pkt_rx_buffer[rx_index++] = ioread32(spdrr);
> > + /* write data */
> > +
> > + if (tx_index < bpw_len)
> > + iowrite32(pkt_tx_buff[tx_index++], spdwr);
> > + }
> > +
> > + /* disable RFI if not needed */
> > + if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
> > + reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
> > +
> > + /* disable RFI */
> > + PCH_CLR_BITMSK(reg_spcr_val, SPCR_RFIE_BIT);
> > +
> > + /* reset rx threshold */
> > + reg_spcr_val &= MASK_RFIC_SPCR_BITS;
> > + reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
> > +
> > + iowrite32(PCH_CLR_BITMSK(reg_spcr_val, SPCR_RFIE_BIT),
> > + (io_remap_addr + PCH_SPCR));
> > + }
> > +
> > + /* update counts */
> > + data->tx_index = tx_index;
> > +
> > + data->rx_index = rx_index;
> > +
> > + }
> > +
> > + /* if transfer complete interrupt */
> > + if (reg_spsr_val & SPSR_FI_BIT) {
> > + /* disable FI & RFI interrupts */
> > + pch_spi_disable_interrupts(data->master, PCH_FI | PCH_RFI);
> > +
> > + /* transfer is completed;inform
> > + pch_spi_process_messages */
> > +
> > + pch_spi_callback(data);
> > + }
> > +}
> > +
> > +
> > +/**
> > + * pch_spi_handler() - Interrupt handler
> > + * @irq: The interrupt number.
> > + * @dev_id: Pointer to struct pch_spi_board_data.
> > + */
> > +static irqreturn_t pch_spi_handler(int irq, void *dev_id)
> > +{
> > + /* channel */
> > + int dev;
> > +
> > + /* SPSR content */
> > + u32 reg_spsr_val;
> > +
> > + /* to hold channel data */
> > + struct pch_spi_data *data;
> > +
> > + /* register addresses */
> > + void __iomem *spsr;
> > +
> > + /* remapped pci base address */
> > + void __iomem *io_remap_addr;
> > +
> > + irqreturn_t ret = IRQ_NONE;
> > +
> > + struct pch_spi_board_data *board_dat =
> > + (struct pch_spi_board_data *)dev_id;
>
> Unnecessary cast because dev_id is already void*
>
> > +
> > + if (board_dat->suspend_sts == true) {
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s returning due to suspend\n", __func__);
> > + } else {
>
> Use this form instead to eliminate the unnecessary else nesting:
>
> if (board_dat->suspend_st == true) {
> dev_dbg(...);
> return IRQ_NONE;
> }
>
>
> > + for (dev = 0; dev < PCH_MAX_DEV; dev++) {
> > + data = board_dat->data[dev];
> > + io_remap_addr = data->io_remap_addr;
> > + spsr = io_remap_addr + PCH_SPSR;
> > +
> > + reg_spsr_val = ioread32(spsr);
> > +
> > + /* Check if the interrupt is for SPI device */
> > +
> > + if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
> > + pch_spi_handler_sub(data, reg_spsr_val,
> > + io_remap_addr);
> > + ret = IRQ_HANDLED;
> > + }
> > + }
>
> This looks sub-optimal for two reasons (this is a comment for the
> whole driver). First, PCH_MAX_DEV is hard coded to 1, so the loop is
> completely redundant.

Yes, you are righht for topcliff.
This code is for other IOH processor.

>
> Second, if this driver does need to handle multiple spi bus instances,
> then it would be better for each bus instance to be registered as a
> separate device that is probed and managed separately. One way to do
> this is for the pci_driver to register a child platform_device for
> each spi bus, and to put all the spi bus driver code into a
> platform_driver which gets it's .probe() hook called for each
> instance.

(We are now discussing)

>
> Regardless, it doesn't look liek the "for (dev = 0; dev < PCH_MAX_DEV;
> dev++)" loops belong in this driver.
>
> > + }
> > +
> > + dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
> > + __func__, ret);
> > +
> > + return ret;
> > +}
> > +
> > +/**
> > + * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
> > + * @master: Pointer to struct spi_master.
> > + * @speed_hz: Baud rate.
> > + */
> > +static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
> > +{
> > + u32 n_spbr, spbrr_val;
> > +
> > + n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
> > +
> > + /* if baud rate is less than we can support limit it */
> > +
> > + if (n_spbr > PCH_MAX_SPBR)
> > + n_spbr = PCH_MAX_SPBR;
> > +
> > + spbrr_val = pch_spi_readreg(master, PCH_SPBRR);
> > +
> > + dev_dbg(&master->dev, "%s SPBRR content=%x SPBR in SPBRR=%d\n",
> > + __func__, spbrr_val, n_spbr);
> > +
> > + /* clear SPBRR */
> > + spbrr_val &= MASK_SPBRR_SPBR_BITS;
> > +
> > + /* set the new value */
> > + spbrr_val |= n_spbr;
> > +
> > + /* write the new value */
> > + pch_spi_writereg(master, PCH_SPBRR, spbrr_val);
> > + dev_dbg(&master->dev, "%s SPBRR content after setting SPBR=%x\n",
> > + __func__, spbrr_val);
> > +}
> > +
> > +/**
> > + * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
> > + * @master: Pointer to struct spi_master.
> > + * @bits_per_word: Bits per word for SPI transfer.
> > + */
> > +static void pch_spi_set_bits_per_word(struct spi_master *master,
> > + u8 bits_per_word)
> > +{
> > + u32 spbrr_val = pch_spi_readreg(master, PCH_SPBRR);
> > + dev_dbg(&master->dev, "%s SPBRR content=%x\n", __func__, spbrr_val);
> > +
> > + if (bits_per_word == PCH_8_BPW) {
> > + PCH_CLR_BITMSK(spbrr_val, SPBRR_SIZE_BIT);
> > + dev_dbg(&master->dev, "%s 8\n", __func__);
> > + } else {
> > + PCH_SET_BITMSK(spbrr_val, SPBRR_SIZE_BIT);
> > + dev_dbg(&master->dev, "%s 16\n", __func__);
> > + }
>
> Use the new pch_spi_setclr_bit() function.
>
> > +
> > + pch_spi_writereg(master, PCH_SPBRR, spbrr_val);
> > +
> > + dev_dbg(&master->dev, "%s SPBRR after setting bits per word=%x\n",
> > + __func__, spbrr_val);
> > +}
> > +
> > +/**
> > + * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
> > + * @master: Pointer to struct spi_master.
> > + */
> > +static void pch_spi_clear_fifo(struct spi_master *master)
> > +{
> > + u32 reg_spcr_val = pch_spi_readreg(master, PCH_SPCR);
> > +
> > + PCH_SET_BITMSK(reg_spcr_val, SPCR_FICLR_BIT);
> > + pch_spi_writereg(master, PCH_SPCR, reg_spcr_val);
> > + dev_dbg(&master->dev, "%s SPCR content after setting FICLR = %x\n",
> > + __func__, reg_spcr_val);
> > +
> > + PCH_CLR_BITMSK(reg_spcr_val, SPCR_FICLR_BIT);
> > + pch_spi_writereg(master, PCH_SPCR, reg_spcr_val);
> > +
> > + dev_dbg(&master->dev, "%s SPCR content after resetting FICLR = %x\n",
> > + __func__, reg_spcr_val);
> > +}
> > +/* ope==true:Set bit, ope==false:Clear bit */
> > +static inline void pch_spi_setclr_bit(u32 *val, u32 pos, u32 ope)
> > +{
> > + if (ope)
> > + PCH_SET_BITMSK(*val, pos);
> > + else
> > + PCH_CLR_BITMSK(*val, pos);
> > +}
>
> Move this function up with your other accessor helpers.
>
> > +
> > +/**
> > + * pch_spi_setup_transfe() - Configures the PCH SPI hardware for transfer
> > + * @spi: Pointer to struct spi_device.
> > + */
> > +static void pch_spi_setup_transfer(struct spi_device *spi)
> > +{
> > + u32 reg_spcr_val;
> > +
> > + dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
> > + __func__, pch_spi_readreg(spi->master, PCH_SPBRR),
> > + spi->max_speed_hz);
> > +
> > + pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
> > +
> > + /* set bits per word */
> > + dev_dbg(&spi->dev, "%s :setting bits_per_word=%d\n",
> > + __func__, spi->bits_per_word);
> > + pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
> > +
> > + dev_dbg(&spi->dev,
> > + "%s SPBRR content after setting baud rate & bits per word=%x\n",
> > + __func__, pch_spi_readreg(spi->master, PCH_SPBRR));
> > +
> > + reg_spcr_val = pch_spi_readreg(spi->master, PCH_SPCR);
> > + dev_dbg(&spi->dev, "%s SPCR content = %x\n", __func__, reg_spcr_val);
> > + /* set bit justification */
> > + pch_spi_setclr_bit(&reg_spcr_val, SPCR_LSBF_BIT,
> > + !(spi->mode & SPI_LSB_FIRST));
> > + pch_spi_setclr_bit(&reg_spcr_val, SPCR_CPOL_BIT, spi->mode & SPI_CPOL);
> > + pch_spi_setclr_bit(&reg_spcr_val, SPCR_CPHA_BIT, spi->mode & SPI_CPHA);
> > +
> > + /* write SPCR SPCR register */
> > + pch_spi_writereg(spi->master, PCH_SPCR, reg_spcr_val);
> > +
> > + dev_dbg(&spi->dev,
> > + "%s SPCR content after setting LSB/MSB and MODE= %x\n",
> > + __func__, reg_spcr_val);
> > +
> > + /* Clear the FIFO by toggling FICLR to 1 and back to 0 */
> > + pch_spi_clear_fifo(spi->master);
> > +}
> > +
> > +/**
> > + * pch_spi_enable_interrupts() - Enables specified interrupts
> > + * @master: Pointer to struct spi_master.
> > + * @interrupt: Interrups to be enabled.
> > + */
> > +static void pch_spi_enable_interrupts(struct spi_master *master, u8
> > interrupt)
> > +{
> > + u32 reg_val_spcr;
> > +
> > + reg_val_spcr = pch_spi_readreg(master, PCH_SPCR);
> > +
> > + dev_dbg(&master->dev, "%s SPCR content=%x\n", __func__, reg_val_spcr);
> > +
> > + if ((interrupt & PCH_RFI) != 0) {
> > + /* set RFIE bit in SPCR */
> > + dev_dbg(&master->dev, "setting RFI in %s\n", __func__);
> > + PCH_SET_BITMSK(reg_val_spcr, SPCR_RFIE_BIT);
> > + }
> > +
> > + if ((interrupt & PCH_TFI) != 0) {
> > + /* set TFIE bit in SPCR */
> > + dev_dbg(&master->dev, "setting TFI in %s\n", __func__);
> > + PCH_SET_BITMSK(reg_val_spcr, SPCR_TFIE_BIT);
> > + }
> > +
> > + if ((interrupt & PCH_FI) != 0) {
> > + /* set FIE bit in SPCR */
> > + dev_dbg(&master->dev, "setting FI in %s\n", __func__);
> > + PCH_SET_BITMSK(reg_val_spcr, SPCR_FIE_BIT);
> > + }
> > +
> > + if ((interrupt & PCH_ORI) != 0) {
> > + /* set ORIE bit in SPCR */
> > + dev_dbg(&master->dev, "setting ORI in %s\n", __func__);
> > + PCH_SET_BITMSK(reg_val_spcr, SPCR_ORIE_BIT);
> > + }
> > +
> > + if ((interrupt & PCH_MDFI) != 0) {
> > + /* set MODFIE bit in SPCR */
> > + dev_dbg(&master->dev, "setting MDFI in %s\n", __func__);
> > + PCH_SET_BITMSK(reg_val_spcr, SPCR_MDFIE_BIT);
> > + }
> > +
> > + pch_spi_writereg(master, PCH_SPCR, reg_val_spcr);
> > +
> > + dev_dbg(&master->dev, "%s SPCR content after enabling interrupt =%x\n",
> > + __func__, reg_val_spcr);
> > +}
>
> Simple function called in only two side-by-side locations. This can
> be removed and replaced with about 4 lines open coded at the call
> site.

Ditto.

>
> > +
> > +/**
> > + * pch_spi_set_threshold() - Sets Tx/Rx FIFO thresholds
> > + * @spi: Pointer to struct spi_device.
> > + * @threshold: Threshold value to be set.
> > + * @dir: Rx or Tx threshold to be set.
> > + */
> > +static void pch_spi_set_threshold(struct spi_device *spi, u32 threshold, u8
> > dir)
> > +{
> > + u32 reg_val_spcr;
> > +
> > + reg_val_spcr = pch_spi_readreg(spi->master, PCH_SPCR);
> > + dev_dbg(&spi->dev, "%s SPCR before modifying =%x threshold=%d\n",
> > + __func__, reg_val_spcr, threshold + 1);
> > +
> > + if (dir == PCH_RX) {
> > + dev_dbg(&spi->dev, "%s setting Rx threshold\n", __func__);
> > + reg_val_spcr &= MASK_RFIC_SPCR_BITS;
> > + reg_val_spcr |= (threshold << SPCR_RFIC_FIELD);
> > + } else if (dir == PCH_TX) {
> > + dev_dbg(&spi->dev, "%s setting Tx threshold\n", __func__);
> > + reg_val_spcr &= MASK_TFIC_SPCR_BITS;
> > + reg_val_spcr |= (threshold << SPCR_TFIC_FIELD);
> > + }
> > +
> > + pch_spi_writereg(spi->master, PCH_SPCR, reg_val_spcr);
> > +
> > + dev_dbg(&spi->dev, "%s SPCR after modifying =%x\n", __func__,
> > + reg_val_spcr);
> > +}
> > +
> > +/**
> > + * pch_spi_reset() - Clears SPI registers
> > + * @master: Pointer to struct spi_master.
> > + */
> > +static void pch_spi_reset(struct spi_master *master)
> > +{
> > + /* write 1 to reset SPI */
> > + pch_spi_writereg(master, PCH_SRST, 0x1);
> > +
> > + /* clear reset */
> > + pch_spi_writereg(master, PCH_SRST, 0x0);
> > +}
> > +
> > +static int pch_spi_setup(struct spi_device *pspi)
> > +{
> > + /* check bits per word */
> > + if ((pspi->bits_per_word) == 0) {
> > + pspi->bits_per_word = PCH_8_BPW;
> > + dev_dbg(&pspi->dev, "%s 8 bits per word\n", __func__);
> > + }
> > +
> > + if (((pspi->bits_per_word) != PCH_8_BPW) &&
> > + ((pspi->bits_per_word != PCH_16_BPW))) {
> > + dev_err(&pspi->dev, "%s Invalid bits per word\n", __func__);
> > + return -EINVAL;
> > + }
> > +
> > + /* Check baud rate setting */
> > + /* if baud rate of chip is greater than
> > + max we can support,return error */
> > + if ((pspi->max_speed_hz) > PCH_MAX_BAUDRATE) {
> > + dev_err(&pspi->dev, "%s Invalid Baud rate\n", __func__);
> > + return -EINVAL;
> > + }
>
> As mentioned before, if the max speed requested is greater than the
> max speed of the bus, then the max bus speed should be used instead.
> This should not cause the transfer to fail.
>
> > +
> > + dev_info(&pspi->dev, "%s MODE = %x\n", __func__,
> > + ((pspi->mode) & (SPI_CPOL | SPI_CPHA)));
>
> I'd be very surprised if you want to have a kernel log message
> generated on each and every spi transfer.
>
> > +
> > + if (((pspi->mode) & SPI_LSB_FIRST) != 0)
> > + dev_dbg(&pspi->dev, "%s LSB_FIRST\n", __func__);
> > + else
> > + dev_dbg(&pspi->dev, "%s MSB_FIRST\n", __func__);
> > +
> > + return 0;
> > +}
> > +
> > +static int pch_spi_transfer(struct spi_device *pspi, struct spi_message
> > *pmsg)
> > +{
> > +
> > + struct spi_transfer *transfer;
> > + struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
> > + int retval;
> > + int ret;
> > +
> > + ret = mutex_lock_interruptible(&pch_spi_mutex);
> > + if (ret) {
> > + retval = -ERESTARTSYS;
> > + goto err_return;
> > + }
>
> The driver shouldn't need the mutex at this point since it is only
> validating the message. Obtaining the mutex can be deferred until
> actually adding the transfer to the list later in the function. (right
> before obtaining the spinlock)
>
> > +
> > + /* validate spi message and baud rate */
> > + if (unlikely((list_empty(&pmsg->transfers) == 1) ||
> > + ((pspi->max_speed_hz) == 0))) {
> > + if (list_empty(&pmsg->transfers) == 1)
> > + dev_err(&pspi->dev, "%s list empty\n", __func__);
> > +
> > + if ((pspi->max_speed_hz) == 0) {
> > + dev_err(&pspi->dev, "%s pch_spi_tranfer maxspeed=%d\n",
> > + __func__, (pspi->max_speed_hz));
> > + }
> > + dev_err(&pspi->dev, "%s returning EINVAL\n", __func__);
> > +
> > + retval = -EINVAL;
> > + goto err_return_mutex;
> > + }
> > +
> > + dev_dbg(&pspi->dev, "%s Transfer List not empty. "
> > + "Transfer Speed is set.\n", __func__);
> > +
> > + /* validate Tx/Rx buffers and Transfer length */
> > + list_for_each_entry(transfer, &pmsg->transfers,
> > + transfer_list) {
> > + if ((((transfer->tx_buf) == NULL)
> > + && ((transfer->rx_buf) == NULL))
> > + || (transfer->len == 0)) {
> > + if (((transfer->tx_buf) == NULL)
> > + && ((transfer->rx_buf) == NULL)) {
> > + dev_err(&pspi->dev,
> > + "%s Tx and Rx buffer NULL\n", __func__);
> > + }
> > +
> > + if (transfer->len == 0) {
> > + dev_err(&pspi->dev, "%s Transfer"
> > + " length invalid\n", __func__);
> > + }
> > +
> > + dev_err(&pspi->dev, "%s returning EINVAL\n", __func__);
> > +
> > + retval = -EINVAL;
> > + goto err_return_mutex;
> > + }
> > +
> > + dev_dbg(&pspi->dev, "%s Tx/Rx buffer valid. Transfer length"
> > + " valid\n", __func__);
> > +
> > + /* if baud rate hs been specified validate the same */
> > + if (transfer->speed_hz) {
> > + if ((transfer->speed_hz) > PCH_MAX_BAUDRATE)
> > + transfer->speed_hz = PCH_MAX_BAUDRATE;
> > + }
> > +
> > + /* if bits per word has been specified validate the same */
> > + if (transfer->bits_per_word) {
> > + if ((transfer->bits_per_word != PCH_8_BPW)
> > + && (transfer->bits_per_word != PCH_16_BPW)) {
> > + retval = -EINVAL;
> > + dev_err(&pspi->dev,
> > + "%s Invalid bits per word\n", __func__);
> > + goto err_return_mutex;
> > + }
> > + }
> > + }
> > +
> > + spin_lock(&data->lock);
> > +
> > + /* We won't process any messages if we have been asked to terminate */
> > +
> > + if (STATUS_EXITING == (data->status)) {
> > + spin_unlock(&data->lock);
> > + dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
> > + retval = -ESHUTDOWN;
> > + goto err_return_spinlock;
> > + }
> > +
> > + /* If suspended ,return -EINVAL */
> > + if (data->board_dat->suspend_sts == true) {
> > + dev_err(&pspi->dev,
> > + "%s bSuspending= true returning EINVAL\n", __func__);
> > + spin_unlock(&data->lock);
> > + retval = -EINVAL;
> > + goto err_return_spinlock;
> > + }
> > +
> > + /* set status of message */
> > + pmsg->actual_length = 0;
> > +
> > + dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
> > +
> > + pmsg->status = -EINPROGRESS;
> > +
> > + /* add message to queue */
> > + list_add_tail(&pmsg->queue, &data->queue);
> > +
> > + dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
> > +
> > + /* schedule work queue to run */
> > + queue_work(data->wk, &data->work);
> > +
> > + dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
> > +
> > + retval = 0;
> > +
> > +err_return_spinlock:
> > + spin_unlock(&data->lock);
> > +err_return_mutex:
> > + mutex_unlock(&pch_spi_mutex);
> > +err_return:
> > + dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
> > + return retval;
> > +}
> > +
> > +static void pch_spi_cleanup(struct spi_device *pspi)
> > +{
> > + dev_dbg(&pspi->dev, "%s\n", __func__);
> > +}
>
> If there are no cleanup operations, then just remove the cleanup hook entirely.
>
> > +
> > +static inline void pch_spi_deselect_chip(struct pch_spi_data *data)
> > +{
> > + if (data->current_chip != NULL)
> > + data->current_chip = NULL;
>
> Redundant if() statement, and this function is only used once. Open
> code at the call site.
>
> > +}
> > +
> > +static inline void pch_spi_select_chip(struct pch_spi_data *data,
> > + struct spi_device *pspi)
> > +{
> > + if ((data->current_chip) != NULL) {
> > + if ((pspi->chip_select) != (data->n_curnt_chip)) {
> > + dev_dbg(&pspi->dev,
> > + "%s : different slave-Invoking\n", __func__);
> > + pch_spi_deselect_chip(data);
> > + }
> > + }
> > +
> > + data->current_chip = pspi;
> > +
> > + data->n_curnt_chip = data->current_chip->chip_select;
> > +
> > + dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
> > + pch_spi_setup_transfer(pspi);
> > +}
> > +
> > +static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
> > + struct spi_message **ppmsg)
> > +{
> > + int b_mem_fail;
> > + int size;
> > + u32 n_writes;
> > + int j;
> > + struct spi_message *pmsg;
> > + pmsg = *ppmsg;
> > +
> > + /* set baud rate if needed */
> > + if (data->cur_trans->speed_hz) {
> > + dev_dbg(&data->master->dev,
> > + "%s:pctrldatasetting baud rate\n", __func__);
> > + pch_spi_set_baud_rate(data->master,
> > + (data->cur_trans->speed_hz));
> > + }
> > +
> > + /* set bits per word if needed */
> > + if ((data->cur_trans->bits_per_word) &&
> > + ((data->current_msg->spi->bits_per_word) !=
> > + (data->cur_trans->bits_per_word))) {
> > + dev_dbg(&data->master->dev,
> > + "%s:setting bits per word\n", __func__);
> > + pch_spi_set_bits_per_word(data->master,
> > + (data->cur_trans->
> > + bits_per_word));
> > + *bpw = data->cur_trans->bits_per_word;
> > + } else {
> > + *bpw = data->current_msg->spi->bits_per_word;
> > + }
> > +
> > + /* reset Tx/Rx index */
> > + data->tx_index = 0;
> > +
> > + data->rx_index = 0;
> > +
> > + if (PCH_8_BPW == *bpw) {
> > + /* 8 bits per word */
> > + data->bpw_len = data->cur_trans->len;
> > + } else {
> > + /* 16 bits per word */
> > + data->bpw_len = (data->cur_trans->len) / 2;
> > + }
> > +
> > + b_mem_fail = false;
> > +
> > + /* find alloc size */
> > + size = (data->cur_trans->len) *
> > + (sizeof(*(data->pkt_tx_buff)));
> > + /* allocate memory for pkt_tx_buff & pkt_rx_buffer */
> > + data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
> > +
> > + if (data->pkt_tx_buff != NULL) {
> > + data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
> > +
> > + if (data->pkt_rx_buff == NULL) {
> > + b_mem_fail = true;
> > + kfree(data->pkt_tx_buff);
> > + }
> > + } else {
> > + b_mem_fail = true;
> > + }
> > +
> > + if (b_mem_fail) {
> > + /* flush queue and set status of all transfers to -ENOMEM */
> > + dev_err(&data->master->dev,
> > + "Kzalloc fail in %s messages\n", __func__);
> > + list_for_each_entry(pmsg, data->queue.next, queue) {
> > + pmsg->status = -ENOMEM;
> > +
> > + if (pmsg->complete != 0)
> > + pmsg->complete(pmsg->context);
> > +
> > + /* delete from queue */
> > + list_del_init(&pmsg->queue);
> > + }
> > +
> > + return;
> > + }
> > +
> > + /* copy Tx Data */
> > + if ((data->cur_trans->tx_buf) != NULL) {
> > + if (PCH_8_BPW == *bpw) {
> > + for (j = 0; j < (data->bpw_len); j++)
> > + data->pkt_tx_buff[j] =
> > + (((u8 *) (data->cur_trans->tx_buf))[j]);
> > + } else {
> > + for (j = 0; j < (data->bpw_len); j++)
> > + data->pkt_tx_buff[j] =
> > + ((u16 *) (data->cur_trans->tx_buf))[j];
> > + }
> > + }
> > +
> > + /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
> > + if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
> > + n_writes = PCH_MAX_FIFO_DEPTH;
> > + else
> > + n_writes = (data->bpw_len);
> > +
> > + dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
> > + "0x2 to SSNXCR\n", __func__);
> > + pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
> > +
> > + dev_dbg(&data->master->dev,
> > + "\n%s:Writing %u items\n", __func__, n_writes);
> > +
> > + for (j = 0; j < n_writes; j++) {
> > + pch_spi_writereg(data->master, PCH_SPDWR,
> > + data->pkt_tx_buff[j]);
> > + }
> > +
> > + /* update tx_index */
> > + data->tx_index = j;
> > + dev_dbg(&data->master->dev, "%s:enabling interrupts\n", __func__);
> > +
> > + /* reset transfer complete flag */
> > + data->transfer_complete = false;
> > + data->transfer_active = true;
> > + dev_dbg(&data->master->dev,
> > + "%s set data->transfer_active = true\n", __func__);
> > +
> > +}
> > +
> > +
> > +static void pch_spi_nomore_transfer(struct pch_spi_data *data,
> > + struct spi_message *pmsg)
> > +{
> > + dev_dbg(&data->master->dev,
> > + "%s:no more transfers in this message\n", __func__);
> > + /* Invoke complete callback
> > + [To the spi core..indicating end of transfer] */
> > + data->current_msg->status = 0;
> > +
> > + if ((data->current_msg->complete) != 0) {
> > + dev_dbg(&data->master->dev,
> > + "%s:Invoking callback of SPI core\n", __func__);
> > + data->current_msg->complete(data->current_msg->context);
> > + }
> > +
> > + /* update status in global variable */
> > + data->bcurrent_msg_processing = false;
> > +
> > + dev_dbg(&data->master->dev,
> > + "%s:data->bcurrent_msg_processing = false\n", __func__);
> > +
> > + data->current_msg = NULL;
> > + data->cur_trans = NULL;
> > +
> > + /* check if we have items in list and not suspending */
> > + /* return 1 if list empty */
> > + if ((list_empty(&data->queue) == 0) &&
> > + (data->board_dat->suspend_sts == false)
> > + && (data->status != STATUS_EXITING)) {
> > + /* We have some more work to do (either there is more tranint
> > + bpw;sfer requests in the current message or there are
> > + more messages)
> > + */
> > + dev_dbg(&data->master->dev,
> > + "%s:we have pending messages-Invoking queue_work\n",
> > + __func__);
> > + queue_work(data->wk, &data->work);
> > + }
> > +
> > + /* check if suspend has been initiated; if yes flush queue */
> > + else if ((data->board_dat->suspend_sts == true) ||
> > + (data->status == STATUS_EXITING)) {
> > + dev_dbg(&data->master->dev,
> > + "%s suspend/remove initiated, flushing queue\n",
> > + __func__);
> > + list_for_each_entry(pmsg, data->queue.next, queue) {
> > + pmsg->status = -EIO;
> > +
> > + if (pmsg->complete != 0)
> > + pmsg->complete(pmsg->context);
> > +
> > + /* delete from queue */
> > + list_del_init(&pmsg->queue);
> > + }
> > + }
> > +}
> > +
> > +static void pch_spi_set_ir(struct pch_spi_data *data)
> > +{
> > + /* enable interrupts */
> > + if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) {
> > + /* set receive threhold to PCH_RX_THOLD */
> > + pch_spi_set_threshold(data->current_chip,
> > + PCH_RX_THOLD,
> > + PCH_RX);
> > + /* enable FI and RFI interrupts */
> > + pch_spi_enable_interrupts(data->master,
> > + PCH_RFI |
> > + PCH_FI);
> > + } else {
> > + /* set receive threhold to maximum */
> > + pch_spi_set_threshold(data->current_chip,
> > + PCH_RX_THOLD_MAX,
> > + PCH_RX);
> > + /* enable FI interrupt */
> > + pch_spi_enable_interrupts(data->master,
> > + PCH_FI);
> > + }
> > +
> > + dev_dbg(&data->master->dev,
> > + "%s:invoking pch_spi_set_enable to enable SPI\n", __func__);
> > +
> > + pch_spi_set_enable((data->current_chip), true);
> > +
> > + /* Wait until the transfer completes; go to sleep after
> > + initiating the transfer. */
> > + dev_dbg(&data->master->dev,
> > + "%s:waiting for transfer to get over\n", __func__);
> > +
> > + wait_event_interruptible(data->wait,
> > + data->transfer_complete != false);
> > +
> > + pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
> > + dev_dbg(&data->master->dev,
> > + "%s:no more control over SSN-writing 0x0 to SSNXCR."
> > + "transmit over.", __func__);
> > +
> > + data->transfer_active = false;
> > + dev_dbg(&data->master->dev,
> > + "%s set data->transfer_active = false\n", __func__);
> > +
> > + /* clear all interrupts */
> > + pch_spi_writereg(data->master, PCH_SPSR,
> > + (pch_spi_readreg(data->master, PCH_SPSR)));
> > + /* disable interrupts */
> > + pch_spi_disable_interrupts(data->master, PCH_ALL);
> > +}
> > +
> > +static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
> > +{
> > + int j;
> > + /* copy Rx Data */
> > + if (!(data->cur_trans->rx_buf))
> > + return;
> > +
> > + if (PCH_8_BPW == bpw) {
> > + for (j = 0; j < (data->bpw_len); j++)
> > + ((u8 *) (data->cur_trans->rx_buf))[j] =
> > + (u8) ((data->pkt_rx_buff[j]) & 0xFF);
> > +
> > + } else {
> > + for (j = 0; j < (data->bpw_len); j++)
> > + ((u16 *) (data->cur_trans->rx_buf))[j] =
> > + (u16) (data->pkt_rx_buff[j]);
> > + }
> > +}
> > +
> > +
> > +static void pch_spi_process_messages(struct work_struct *pwork)
> > +{
> > + struct spi_message *pmsg;
> > + int bpw;
> > +
> > + struct pch_spi_data *data =
> > + container_of(pwork, struct pch_spi_data, work);
> > + dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
> > +
> > + spin_lock(&data->lock);
> > +
> > + /* check if suspend has been initiated;if yes flush queue */
> > + if ((data->board_dat->suspend_sts) ||
> > + (data->status == STATUS_EXITING)) {
> > + dev_dbg(&data->master->dev,
> > + "%s suspend/remove initiated,flushing queue\n",
> > + __func__);
> > + list_for_each_entry(pmsg, data->queue.next, queue) {
> > + pmsg->status = -EIO;
> > +
> > + if (pmsg->complete != 0) {
> > + spin_unlock(&data->lock);
> > + pmsg->complete(pmsg->context);
> > + spin_lock(&data->lock);
> > + }
> > +
> > + /* delete from queue */
> > + list_del_init(&pmsg->queue);
> > + }
> > +
> > + spin_unlock(&data->lock);
> > + return;
> > + }
> > +
> > + data->bcurrent_msg_processing = true;
> > + dev_dbg(&data->master->dev,
> > + "%s Set data->bcurrent_msg_processing= true\n", __func__);
> > +
> > + /* Get the message from the queue and delete it from there. */
> > + data->current_msg =
> > + list_entry(data->queue.next, struct spi_message, queue);
> > +
> > + list_del_init(&data->current_msg->queue);
> > +
> > + data->current_msg->status = 0;
> > +
> > + pch_spi_select_chip(data, data->current_msg->spi);
> > +
> > + spin_unlock(&data->lock);
> > +
> > + do {
> > + /* If we are already processing a message get the next
> > + transfer structure from the message otherwise retrieve
> > + the 1st transfer request from the message. */
> > + spin_lock(&data->lock);
> > +
> > + if (data->cur_trans == NULL) {
> > + data->cur_trans =
> > + list_entry(data->current_msg->transfers.
> > + next, struct spi_transfer,
> > + transfer_list);
> > + dev_dbg(&data->master->dev,
> > + "%s :Getting 1st transfer message\n", __func__);
> > + } else {
> > + data->cur_trans =
> > + list_entry(data->cur_trans->
> > + transfer_list.next,
> > + struct spi_transfer,
> > + transfer_list);
> > + dev_dbg(&data->master->dev,
> > + "%s :Getting next transfer message\n",
> > + __func__);
> > + }
> > +
> > + spin_unlock(&data->lock);
> > +
> > + pch_spi_set_tx(data, &bpw, &pmsg);
> > +
> > + /* Control interrupt*/
> > + pch_spi_set_ir(data);
> > +
> > + /* Disable SPI transfer */
> > + pch_spi_set_enable((data->current_chip), false);
> > +
> > + /* clear FIFO */
> > + pch_spi_clear_fifo(data->master);
> > +
> > + /* copy Rx Data */
> > + pch_spi_copy_rx_data(data, bpw);
> > +
> > + /* free memory */
> > + kfree(data->pkt_rx_buff);
> > + if (data->pkt_rx_buff)
> > + data->pkt_rx_buff = NULL;
> > +
> > + kfree(data->pkt_tx_buff);
> > + if (data->pkt_tx_buff)
> > + data->pkt_tx_buff = NULL;
> > +
> > + /* increment message count */
> > + data->current_msg->actual_length +=
> > + data->cur_trans->len;
> > +
> > + dev_dbg(&data->master->dev,
> > + "%s:data->current_msg->actual_length=%d\n",
> > + __func__, data->current_msg->actual_length);
> > +
> > + /* check for delay */
> > + if (data->cur_trans->delay_usecs) {
> > + dev_dbg(&data->master->dev, "%s:"
> > + "delay in usec=%d\n", __func__,
> > + data->cur_trans->delay_usecs);
> > + udelay(data->cur_trans->delay_usecs);
> > + }
> > +
> > + spin_lock(&data->lock);
> > +
> > + /* No more transfer in this message. */
> > + if ((data->cur_trans->transfer_list.next) ==
> > + &(data->current_msg->transfers)) {
> > + pch_spi_nomore_transfer(data, pmsg);
> > + }
> > +
> > + spin_unlock(&data->lock);
> > +
> > + } while ((data->cur_trans) != NULL);
> > +}
> > +
> > +static void pch_spi_free_resources(struct pch_spi_board_data *board_dat)
> > +{
> > + int i;
> > +
> > + dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
> > +
> > + /* free workqueue */
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + if (board_dat->data[i]->wk != NULL) {
> > + destroy_workqueue(board_dat->data[i]->wk);
> > + board_dat->data[i]->wk = NULL;
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s destroy_workqueue invoked successfully\n",
> > + __func__);
> > + }
> > + }
> > +
> > + /* disable interrupts & free IRQ */
> > + if (board_dat->irq_reg_sts == true) {
> > + /* disable interrupts */
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + pch_spi_disable_interrupts(board_dat->data[i]->
> > + master, PCH_ALL);
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s pch_spi_disable_interrupts invoked "
> > + "successfully\n", __func__);
> > + }
> > +
> > + /* free IRQ */
> > + free_irq(board_dat->pdev->irq, (void *)board_dat);
> > +
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s free_irq invoked successfully\n", __func__);
> > +
> > + board_dat->irq_reg_sts = false;
> > + }
> > +
> > + /* unmap PCI base address */
> > + if ((board_dat->data[0]->io_remap_addr) != 0) {
> > + pci_iounmap(board_dat->pdev,
> > + board_dat->data[0]->io_remap_addr);
> > +
> > + for (i = 0; i < PCH_MAX_DEV; i++)
> > + board_dat->data[i]->io_remap_addr = 0;
> > +
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s pci_iounmap invoked successfully\n", __func__);
> > + }
> > +
> > + /* release PCI region */
> > + if (board_dat->pci_req_sts == true) {
> > + pci_release_regions(board_dat->pdev);
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s pci_release_regions invoked successfully\n",
> > + __func__);
> > + board_dat->pci_req_sts = false;
> > + }
> > +}
> > +
> > +static int pch_spi_get_resources(struct pch_spi_board_data *board_dat)
> > +{
> > + int i, j, m, n;
> > + void __iomem *io_remap_addr;
> > + int retval;
> > + dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
> > +
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + /* iniatize queue of pending messages */
> > + INIT_LIST_HEAD(&(board_dat->data[i]->queue));
> > +
> > + /* initialize spin locks */
> > + spin_lock_init(&(board_dat->data[i]->lock));
> > +
> > + /* set channel status */
> > + board_dat->data[i]->status = STATUS_RUNNING;
> > +
> > + /* initialize work structure */
> > + INIT_WORK(&(board_dat->data[i]->work),
> > + pch_spi_process_messages);
> > +
> > + /* initialize wait queues */
> > + init_waitqueue_head(&(board_dat->data[i]->wait));
> > + }
> > +
> > + for (j = 0, retval = 0; j < PCH_MAX_DEV; j++) {
> > + /* create workqueue */
> > + board_dat->data[j]->wk =
> > + create_singlethread_workqueue(DRIVER_NAME);
> > +
> > + if ((board_dat->data[j]->wk) == NULL) {
> > + dev_err(&board_dat->pdev->dev,
> > + "%s create_singlet hread_workqueue failed\n",
> > + __func__);
> > + retval = -EBUSY;
> > + goto err_return;
> > + }
> > + }
> > +
> > + if (retval != 0)
> > + goto err_return;
> > +
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s create_singlethread_workqueue success\n", __func__);
> > +
> > + retval = pci_request_regions(board_dat->pdev, DRIVER_NAME);
> > + if (retval != 0) {
> > + dev_err(&board_dat->pdev->dev,
> > + "%s request_region failed\n", __func__);
> > + goto err_return;
> > + }
> > +
> > + board_dat->pci_req_sts = true;
> > +
> > + io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
> > +
> > + if (io_remap_addr == 0) {
> > + dev_err(&board_dat->pdev->dev,
> > + "%s pci_iomap failed\n", __func__);
> > + retval = -ENOMEM;
> > + goto err_return;
> > + }
> > +
> > + /* calculate base address for all channels */
> > + for (m = 0; m < PCH_MAX_DEV; m++) {
> > + board_dat->data[m]->io_remap_addr =
> > + io_remap_addr + (PCH_ADDRESS_SIZE * m);
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s Base address for channel %d= %x\n", __func__, m ,
> > + (u32)(board_dat->data[m]->io_remap_addr));
> > + }
> > +
> > + /* reset PCH SPI h/w */
> > + for (n = 0; n < PCH_MAX_DEV; n++) {
> > + pch_spi_reset(board_dat->data[n]->master);
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s pch_spi_reset invoked successfully\n", __func__);
> > + }
> > +
> > + /* register IRQ */
> > + retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
> > + IRQF_SHARED, DRIVER_NAME, (void *)board_dat);
> > + if (retval != 0) {
> > + dev_err(&board_dat->pdev->dev,
> > + "%s request_irq failed\n", __func__);
> > + goto err_return;
> > + }
> > +
> > + dev_dbg(&board_dat->pdev->dev, "%s request_irq returned=%d\n",
> > + __func__, retval);
> > +
> > + board_dat->irq_reg_sts = true;
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s data->irq_reg_sts=true\n", __func__);
> > +
> > +err_return:
> > + if (retval != 0) {
> > + dev_err(&board_dat->pdev->dev,
> > + "%s FAIL:invoking pch_spi_free_resources\n", __func__);
> > + pch_spi_free_resources(board_dat);
> > + }
> > +
> > + dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
> > +
> > + return retval;
> > +}
> > +
> > +static int
> > +pch_spi_check_request_pending(struct pch_spi_board_data *board_dat)
> > +{
> > + int i;
> > + int sts;
> > + u16 count;
> > +
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + count = 500;
> > + spin_lock(&(board_dat->data[i]->lock));
> > + board_dat->data[i]->status = STATUS_EXITING;
> > +
> > + while ((list_empty(&(board_dat->data[i]->queue)) == 0) &&
> > + (--count)) {
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s :queue not empty\n", __func__);
> > + spin_unlock(&(board_dat->data[i]->lock));
> > + msleep(PCH_SLEEP_TIME);
> > + spin_lock(&(board_dat->data[i]->lock));
> > + }
> > +
> > + spin_unlock(&(board_dat->data[i]->lock));
> > +
> > + if (count) {
> > + sts = 0;
> > + dev_dbg(&board_dat->pdev->dev,
> > + "%s :queue empty\n", __func__);
> > + } else {
> > + sts = -EBUSY;
> > + }
> > + }
> > +
> > + dev_dbg(&board_dat->pdev->dev, "%s : EXIT=%d\n", __func__, sts);
> > +
> > + return sts;
> > +}
> > +
> > +static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id
> > *id)
> > +{
> > +
> > + struct spi_master *master[PCH_MAX_DEV];
> > +
> > + struct pch_spi_board_data *board_dat;
> > + int retval, i, j, k, l, m;
>
> As already mentioned; don't use a separate loop index for each and
> every non-nested for-loop. It is safe to reuse 'i'.
>
> > + int spi_alloc_num, spi_master_num;
> > +
> > + dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
> > +
> > + /* allocate memory for private data */
> > + board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
> > +
> > + if (board_dat == NULL) {
> > + dev_err(&pdev->dev,
> > + " %s memory allocation for private data failed\n",
> > + __func__);
> > + retval = -ENOMEM;
> > + goto err_kmalloc;
> > + }
> > +
> > + dev_dbg(&pdev->dev,
> > + "%s memory allocation for private data success\n", __func__);
> > +
> > + /* enable PCI device */
> > + retval = pci_enable_device(pdev);
> > + if (retval != 0) {
> > + dev_err(&pdev->dev, "%s pci_enable_device FAILED\n", __func__);
> > +
> > + goto err_pci_en_device;
> > + }
> > +
> > + dev_dbg(&pdev->dev, "%s pci_enable_device returned=%d\n",
> > + __func__, retval);
> > +
> > + board_dat->pdev = pdev;
> > +
> > + /* alllocate memory for SPI master */
> > + for (i = 0, spi_alloc_num = 0; i < PCH_MAX_DEV; i++, spi_alloc_num++) {
> > + master[i] = spi_alloc_master(&pdev->dev,
> > + sizeof(struct pch_spi_data));
> > +
> > + if (master[i] == NULL) {
> > + retval = -ENOMEM;
> > + dev_err(&pdev->dev, "%s [ch=%d]Fail.\n", __func__, i);
> > + goto err_spi_alloc_master;
> > + }
> > + }
> > +
> > + dev_dbg(&pdev->dev,
> > + "%s spi_alloc_master returned non NULL\n", __func__);
> > +
> > + /* initialize members of SPI master */
> > + for (j = 0, spi_master_num = 0; j < PCH_MAX_DEV;
> > + j++, spi_master_num++) {
> > + master[j]->bus_num = 0;
>
> bus_num = -1. Let the spi layer dynamically assign the bus number.
> There may also be other SPI busses in the system, so you cannot hard
> code bus numbers in this driver anyway.

With x86, can our spi-driver get bus_num dynamically ?

>
> > + master[j]->num_chipselect = PCH_MAX_CS;
> > + master[j]->setup = pch_spi_setup;
> > + dev_dbg(&pdev->dev,
> > + "%s setup member of SPI master initialized\n",
> > + __func__);
> > + master[j]->transfer = pch_spi_transfer;
> > + dev_dbg(&pdev->dev,
> > + "%s transfer member of SPI master initialized\n",
> > + __func__);
> > + master[j]->cleanup = pch_spi_cleanup;
> > + dev_dbg(&pdev->dev,
> > + "%s cleanup member of SPI master initialized\n",
> > + __func__);
> > +
> > + board_dat->data[j] =
> > + spi_master_get_devdata(master[j]);
> > +
> > + board_dat->data[j]->master = master[j];
> > + board_dat->data[j]->n_curnt_chip = 255;
> > + board_dat->data[j]->current_chip = NULL;
> > + board_dat->data[j]->transfer_complete = false;
> > + board_dat->data[j]->pkt_tx_buff = NULL;
> > + board_dat->data[j]->pkt_rx_buff = NULL;
> > + board_dat->data[j]->tx_index = 0;
> > + board_dat->data[j]->rx_index = 0;
> > + board_dat->data[j]->transfer_active = false;
> > + board_dat->data[j]->board_dat = board_dat;
> > + board_dat->suspend_sts = false;
> > +
> > + /* Register the controller with the SPI core. */
> > + retval = spi_register_master(master[j]);
> > + if (retval != 0) {
> > + dev_err(&pdev->dev,
> > + "%s spi_register_master FAILED\n", __func__);
> > + goto err_spi_reg_master;
> > + }
> > +
> > + dev_dbg(&pdev->dev, "%s spi_register_master returned=%d\n",
> > + __func__, retval);
> > + }
>
> Registering the bus should be the *last* thing that happens. SPI
> transfers can begin the moment the device is registered, so all the
> setup code below this point needs to be completed before registering
> the bus.
>
> > +
> > + /* allocate resources for PCH SPI */
> > + retval = pch_spi_get_resources(board_dat);
> > + if (retval != 0) {
> > + dev_err(&pdev->dev, "%s fail(retval=%d)\n",
> > + __func__, retval);
> > + goto err_spi_get_resources;
> > + }
> > +
> > + dev_dbg(&pdev->dev, "%s pch_spi_get_resources returned=%d\n",
> > + __func__, retval);
> > +
> > + /* save private data in dev */
> > + pci_set_drvdata(pdev, (void *)board_dat);
> > + dev_dbg(&pdev->dev, "%s invoked pci_set_drvdata\n", __func__);
> > +
> > + /* set master mode */
> > + for (k = 0; k < PCH_MAX_DEV; k++) {
> > + pch_spi_set_master_mode(master[k]);
> > + dev_dbg(&pdev->dev,
> > + "%s invoked pch_spi_set_master_mode\n", __func__);
> > + }
> > +
> > + return 0;
> > +
> > +err_spi_get_resources:
> > + for (l = 0; l <= spi_master_num; l++)
> > + spi_unregister_master(master[l]);
> > +err_spi_reg_master:
> > +err_spi_alloc_master:
> > + for (m = 0; m <= spi_alloc_num; m++)
> > + spi_master_put(master[m]);
> > + pci_disable_device(pdev);
> > +err_pci_en_device:
> > + kfree(board_dat);
> > +err_kmalloc:
> > + return retval;
> > +}
> > +
> > +static void pch_spi_remove(struct pci_dev *pdev)
> > +{
> > + int i;
> > +
> > + struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
> > +
> > + dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
> > +
> > + if (!board_dat) {
> > + dev_err(&pdev->dev,
> > + "%s pci_get_drvdata returned NULL\n", __func__);
> > + return;
> > + }
> > +
> > + /* check for any pending messages */
> > + if ((-EBUSY) == pch_spi_check_request_pending(board_dat)) {
> > + dev_dbg(&pdev->dev,
> > + "%s pch_spi_check_request_pending returned"
> > + " EBUSY\n", __func__);
> > + /* no need to take any particular action; proceed with remove
> > + even though queue is not empty */
> > + }
> > +
> > + dev_dbg(&pdev->dev,
> > + "%s pch_spi_check_request_pending invoked\n", __func__);
> > +
> > + /* Free resources allocated for PCH SPI */
> > + pch_spi_free_resources(board_dat);
> > + dev_dbg(&pdev->dev,
> > + "%s invoked pch_spi_free_resources\n", __func__);
> > +
> > + /* Unregister SPI master */
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + spi_unregister_master(board_dat->data[i]->
> > + master);
> > + dev_dbg(&pdev->dev,
> > + "%s invoked spi_unregister_master\n", __func__);
> > + }
> > +
> > + /* free memory for private data */
> > + kfree(board_dat);
> > +
> > + pci_set_drvdata(pdev, NULL);
> > +
> > + dev_dbg(&pdev->dev,
> > + "%s memory for private data freed\n", __func__);
> > +
> > + /* disable PCI device */
> > + pci_disable_device(pdev);
> > +
> > + dev_dbg(&pdev->dev,
> > + "%s invoked pci_disable_device\n", __func__);
> > +}
> > +
> > +#ifdef CONFIG_PM
> > +static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
> > +{
> > + int i;
> > + u8 count;
> > + int retval;
> > +
> > + struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
> > +
> > + dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
> > +
> > + if (!board_dat) {
> > + dev_err(&pdev->dev,
> > + "%s pci_get_drvdata returned NULL\n", __func__);
> > + return -EFAULT;
> > + }
> > +
> > + retval = 0;
> > + dev_dbg(&pdev->dev,
> > + "%s pci_get_drvdata invoked successfully\n", __func__);
> > + board_dat->suspend_sts = true;
> > + dev_dbg(&pdev->dev,
> > + "%s board_dat->bSuspending set to true\n", __func__);
> > +
> > + /* check if the current message is processed:
> > + Only after thats done the transfer will be suspended */
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + count = 255;
> > +
> > + while ((--count) > 0) {
> > + if (board_dat->data[i]->
> > + bcurrent_msg_processing == false) {
> > + dev_dbg(&pdev->dev, "%s board_dat->"
> > + "data->bCurrent_"
> > + "msg_processing = false\n",
> > + __func__);
> > + break;
> > + } else {
> > + dev_dbg(&pdev->dev, "%s board_dat->"
> > + "data->bCurrent_msg_"
> > + "processing = true\n",
> > + __func__);
> > + }
> > + msleep(PCH_SLEEP_TIME);
> > + }
> > + }
> > +
> > + /* Free IRQ */
> > + if (board_dat->irq_reg_sts == true) {
> > + /* disable all interrupts */
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + pch_spi_disable_interrupts(board_dat->data[i]->
> > + master,
> > + PCH_ALL);
> > + pch_spi_reset(board_dat->data[i]->master);
> > + dev_dbg(&pdev->dev,
> > + "%s pch_spi_disable_interrupts invoked"
> > + "successfully\n", __func__);
> > + }
> > +
> > + free_irq(board_dat->pdev->irq, (void *)board_dat);
> > +
> > + board_dat->irq_reg_sts = false;
> > + dev_dbg(&pdev->dev,
> > + "%s free_irq invoked successfully."
> > + "data->irq_reg_sts = false\n",
> > + __func__);
> > + }
> > +
> > + /* save config space */
> > + retval = pci_save_state(pdev);
> > +
> > + if (retval == 0) {
> > + dev_dbg(&pdev->dev, "%s pci_save_state returned=%d\n",
> > + __func__, retval);
> > + /* disable PM notifications */
> > + pci_enable_wake(pdev, PCI_D3hot, 0);
> > + dev_dbg(&pdev->dev,
> > + "%s pci_enable_wake invoked successfully\n", __func__);
> > + /* disable PCI device */
> > + pci_disable_device(pdev);
> > + dev_dbg(&pdev->dev,
> > + "%s pci_disable_device invoked successfully\n",
> > + __func__);
> > + /* move device to D3hot state */
> > + pci_set_power_state(pdev, PCI_D3hot);
> > + dev_dbg(&pdev->dev,
> > + "%s pci_set_power_state invoked successfully\n",
> > + __func__);
> > + } else {
> > + dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
> > + }
> > +
> > + dev_dbg(&pdev->dev, "%s return=%d\n", __func__, retval);
> > +
> > + return retval;
> > +}
> > +
> > +static int pch_spi_resume(struct pci_dev *pdev)
> > +{
> > + int i;
> > + int retval;
> > +
> > + struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
> > + dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
> > +
> > + if (!board_dat) {
> > + dev_err(&pdev->dev,
> > + "%s pci_get_drvdata returned NULL\n", __func__);
> > + return -EFAULT;
> > + }
> > +
> > + retval = 0;
> > + /* move device to DO power state */
> > + pci_set_power_state(pdev, PCI_D0);
> > +
> > + /* restore state */
> > + pci_restore_state(pdev);
> > +
> > + retval = pci_enable_device(pdev);
> > + if (retval < 0) {
> > + dev_err(&pdev->dev,
> > + "%s pci_enable_device failed\n", __func__);
>
> if (retval < 0) {
> return retval;
> dev_err(...);
> }
>
> > + } else {
> > + /* disable PM notifications */
> > + pci_enable_wake(pdev, PCI_D3hot, 0);
> > +
> > + /* register IRQ handler */
> > + if ((board_dat->irq_reg_sts) != true) {
> > + /* register IRQ */
> > + retval = request_irq(board_dat->pdev->irq,
> > + pch_spi_handler, IRQF_SHARED,
> > + DRIVER_NAME, board_dat);
> > + if (retval < 0) {
> > + dev_err(&pdev->dev,
> > + "%s request_irq failed\n", __func__);
> > + } else {
> > + board_dat->irq_reg_sts = true;
> > +
> > + /* reset PCH SPI h/w */
> > + for (i = 0; i < PCH_MAX_DEV; i++) {
> > + pch_spi_reset(board_dat->data[i]->
> > + master);
> > + pch_spi_set_master_mode
> > + (board_dat->data[i]->master);
> > + }
> > +
> > + /* set suspend status to false */
> > + board_dat->suspend_sts = false;
> > +
> > + }
> > + }
> > + }
> > +
> > + dev_dbg(&pdev->dev, "%s returning=%d\n", __func__, retval);
> > +
> > + return retval;
> > +}
> > +#else
> > +#define pch_spi_suspend NULL
> > +#define pch_spi_resume NULL
> > +
> > +#endif
> > +
> > +static struct pci_driver pch_spi_pcidev = {
> > + .name = "pch_spi",
> > + .id_table = pch_spi_pcidev_id,
> > + .probe = pch_spi_probe,
> > + .remove = pch_spi_remove,
> > + .suspend = pch_spi_suspend,
> > + .resume = pch_spi_resume,
> > +};
> > +
> > +static int __init pch_spi_init(void)
> > +{
> > + return pci_register_driver(&pch_spi_pcidev);
> > +}
> > +
> > +
> > +static void __exit pch_spi_exit(void)
> > +{
> > + pci_unregister_driver(&pch_spi_pcidev);
> > +}
> > +
> > +MODULE_LICENSE("GPL");
> > +MODULE_DESCRIPTION("PCH SPI PCI Driver");
> > +module_init(pch_spi_init);
> > +module_exit(pch_spi_exit);
> > +
> > diff --git a/drivers/spi/spi_pch.h b/drivers/spi/spi_pch.h
> > new file mode 100644
> > index 0000000..aab4411
> > --- /dev/null
> > +++ b/drivers/spi/spi_pch.h
>
> This header file needs to be rolled into the drivers/spi/spi_pch.c file.
>
> > diff --git a/drivers/spi/spi_pch_device.c b/drivers/spi/spi_pch_device.c
> > new file mode 100644
> > index 0000000..853aee9
> > --- /dev/null
> > +++ b/drivers/spi/spi_pch_device.c
> > @@ -0,0 +1,56 @@
> > +/*
> > + * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; version 2 of the License.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > + * GNU General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License
> > + * along with this program; if not, write to the Free Software
> > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307,
> > USA.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/spi/spidev.h>
> > +#include <linux/device.h>
> > +#include <linux/spi/spi.h>
> > +
> > +static struct spi_board_info pch_spi_slaves[] = {
> > + {
> > + .modalias = "spidev",
> > + .max_speed_hz = 1000000,
> > + .bus_num = 0,
> > + .chip_select = 0,
> > + .platform_data = NULL,
> > + .mode = SPI_MODE_0,
> > + },
> > +#if (CONFIG_PCH_SPI_PLATFORM_DEVICE_COUNT == 2)
> > + {
> > + .modalias = "spidev",
> > + .max_speed_hz = 1000000,
> > + .bus_num = 1,
> > + .chip_select = 1,
> > + .platform_data = NULL,
> > + .mode = SPI_MODE_0,
> > + },
> > +#endif
> > +};
> > +
> > +static __init int pch_init(void)
> > +{
> > + int rc = -1;
> > +
> > + if (!spi_register_board_info
> > + (pch_spi_slaves, ARRAY_SIZE(pch_spi_slaves)))
> > + rc = 0;
> > +
> > + return rc;
> > +}
>
> As mentioned at top of email, this is the wrong way to register spi
> bus data. It needs to be done in the platform setup code (need
> feedback from tglx and dwmw2 on how best to do this).
>

Thanks, Ohtake(OKISemi)


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