Hi, On Tue, 2013-09-10 at 08:46 -0500, Josh Cartwright wrote: > Hey Ivan- > > Some nits below. > > On Thu, Aug 29, 2013 at 04:27:53PM +0300, Ivan T. Ivanov wrote: > > From: "Ivan T. Ivanov" <[email protected]> > > > > This bus driver supports the QUP i2c hardware controller in the Qualcomm > > MSM SOCs. The Qualcomm Universal Peripheral Engine (QUP) is a general > > purpose data path engine with input/output FIFOs and an embedded i2c > > mini-core. The driver supports FIFO mode (for low bandwidth applications) > > Rogue tab in your commit message.
Will fix. > > > and block mode (interrupt generated for each block-size data transfer). > > The driver currently does not support DMA transfers. > > > > Shamelessly based on codeaurora version of the driver. > > > > This controller could be found in the following chip-sets: > > msm9625, msm8974, msm8610, msm8226, mpq8092. > > This may be good to include in the Kconfig help text. Will do. > > > Signed-off-by: Ivan T. Ivanov <[email protected]> > > --- > > drivers/i2c/busses/Kconfig | 10 + > > drivers/i2c/busses/Makefile | 1 + > > drivers/i2c/busses/i2c-qup.c | 909 > > ++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 920 insertions(+) > > create mode 100644 drivers/i2c/busses/i2c-qup.c > > > > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > > index fcdd321..c76ddd4 100644 > > --- a/drivers/i2c/busses/Kconfig > > +++ b/drivers/i2c/busses/Kconfig > > @@ -777,6 +777,16 @@ config I2C_RCAR > > This driver can also be built as a module. If so, the module > > will be called i2c-rcar. > > > > +config I2C_QUP > > + tristate "Qualcomm QUP based I2C controller" > > + depends on ARCH_MSM > > + help > > + If you say yes to this option, support will be included for the > > + built-in I2C interface on the MSM family processors. > > + > > + This driver can also be built as a module. If so, the module > > + will be called i2c-qup. > > + > > comment "External I2C/SMBus adapter drivers" > > > > config I2C_DIOLAN_U2C > > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > > index d00997f..77127df 100644 > > --- a/drivers/i2c/busses/Makefile > > +++ b/drivers/i2c/busses/Makefile > > @@ -76,6 +76,7 @@ obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o > > obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o > > obj-$(CONFIG_I2C_XLR) += i2c-xlr.o > > obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o > > +obj-$(CONFIG_I2C_QUP) += i2c-qup.o > > > > # External I2C/SMBus adapter drivers > > obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o > > diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c > > new file mode 100644 > > index 0000000..3b5ef91 > > --- /dev/null > > +++ b/drivers/i2c/busses/i2c-qup.c > [..] > > + > > +static int qup_i2c_change_state(struct qup_i2c_dev *qup, u32 state) > > +{ > > + if (qup_i2c_poll_state(qup, 0, true) != 0) > > + return -EIO; > > + > > + writel(state, qup->base + QUP_STATE); > > + > > + if (qup_i2c_poll_state(qup, state, false) != 0) > > + return -EIO; > > + return 0; > > +} > > + > > +static void qup_i2c_enable(struct qup_i2c_dev *qup, bool state) > > Bit of a confusing name, especially when qup_i2c_enable(qup, false) is > used. I'd suggest qup_i2c_set_state or qup_i2c_set_enabled. Indeed. I prefer qup_i2c_set_enabled. > > > +{ > > + u32 config; > > + > > + if (state) { > > + clk_prepare_enable(qup->clk); > > + clk_prepare_enable(qup->pclk); > > + } else { > > + qup_i2c_change_state(qup, QUP_RESET_STATE); > > + clk_disable_unprepare(qup->clk); > > + config = readl(qup->base + QUP_CONFIG); > > + config |= QUP_CLOCK_AUTO_GATE; > > + writel(config, qup->base + QUP_CONFIG); > > + clk_disable_unprepare(qup->pclk); > > + } > > +} > [..] > > +static int qup_i2c_probe(struct platform_device *pdev) > > +{ > [..] > > + > > + ret = devm_request_irq(qup->dev, qup->irq, qup_i2c_interrupt, > > + IRQF_TRIGGER_HIGH, "i2c_qup", qup); > > + if (ret) { > > + dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq); > > + return ret; > > + } > > + > > + disable_irq(qup->irq); > > How is this not racy, in the case where a pending interrupt is left from > the bootloader (which seems to be possible based on the comments below)? Yes it looks weird. Interrupt handler will check and exit if there is no message for transfer. I am looking for better way to handle this. Thanks, Ivan > > > + > > + init_completion(&qup->xfer); > > + > > + ret = clk_set_rate(qup->clk, qup->src_clk_freq); > > + if (ret) > > + dev_info(qup->dev, "Fail to set core clk, %dHz:%d\n", > > + qup->src_clk_freq, ret); > > + > > + qup_i2c_enable(qup, true); > > + > > + /* > > + * If bootloaders leave a pending interrupt on certain QUP's, > > + * then we reset the core before registering for interrupts. > > + */ > [..] > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
