Re: [PATCH linux-next v11 3/3] mfd: atmel-flexcom: add a driver for Atmel Flexible Serial Communication Unit

2015-10-01 Thread Lee Jones 
On Mon, 28 Sep 2015, Cyrille Pitchen wrote:

> This driver supports the new Atmel Flexcom. The Flexcom is a wrapper which
> integrates one SPI controller, one I2C controller and one USART. Only one
> function can be enabled at a time. This driver selects the function once
> for all, when the Flexcom is probed, according to the value of the new
> "atmel,flexcom-mode" device tree property.
> 
> This driver has chosen to present the Flexcom to the system as a MFD so
> the implementation is seamless for the existing Atmel SPI, I2C and USART
> drivers.
> 
> Also the Flexcom embeds FIFOs: the latest patches of the SPI, I2C and
> USART drivers take advantage of this new feature.
> 
> Signed-off-by: Cyrille Pitchen 
> Acked-by: Boris Brezillon 
> Acked-by: Alexandre Belloni 
> Acked-by: Nicolas Ferre 
> ---
>  drivers/mfd/Kconfig |  11 +
>  drivers/mfd/Makefile|   1 +
>  drivers/mfd/atmel-flexcom.c | 104 
> 
>  3 files changed, 116 insertions(+)
>  create mode 100644 drivers/mfd/atmel-flexcom.c

Applied, thanks.

> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 99d63675f073..87e84e7c71da 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -60,6 +60,17 @@ config MFD_AAT2870_CORE
> additional drivers must be enabled in order to use the
> functionality of the device.
>  
> +config MFD_ATMEL_FLEXCOM
> + tristate "Atmel Flexcom (Flexible Serial Communication Unit)"
> + select MFD_CORE
> + depends on OF
> + help
> +   Select this to get support for Atmel Flexcom. This is a wrapper
> +   which embeds a SPI controller, a I2C controller and a USART. Only
> +   one function can be used at a time. The choice is done at boot time
> +   by the probe function of this MFD driver according to a device tree
> +   property.
> +
>  config MFD_ATMEL_HLCDC
>   tristate "Atmel HLCDC (High-end LCD Controller)"
>   select MFD_CORE
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index d6c21e3c409f..a8b76b81b467 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -164,6 +164,7 @@ obj-$(CONFIG_MFD_SPMI_PMIC)   += qcom-spmi-pmic.o
>  obj-$(CONFIG_TPS65911_COMPARATOR)+= tps65911-comparator.o
>  obj-$(CONFIG_MFD_TPS65090)   += tps65090.o
>  obj-$(CONFIG_MFD_AAT2870_CORE)   += aat2870-core.o
> +obj-$(CONFIG_MFD_ATMEL_FLEXCOM)  += atmel-flexcom.o
>  obj-$(CONFIG_MFD_ATMEL_HLCDC)+= atmel-hlcdc.o
>  obj-$(CONFIG_MFD_INTEL_LPSS) += intel-lpss.o
>  obj-$(CONFIG_MFD_INTEL_LPSS_PCI) += intel-lpss-pci.o
> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
> new file mode 100644
> index ..e8e67be6b493
> --- /dev/null
> +++ b/drivers/mfd/atmel-flexcom.c
> @@ -0,0 +1,104 @@
> +/*
> + * Driver for Atmel Flexcom
> + *
> + * Copyright (C) 2015 Atmel Corporation
> + *
> + * Author: Cyrille Pitchen 
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * 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, see .
> + */
> +
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +
> +/* I/O register offsets */
> +#define FLEX_MR  0x0 /* Mode Register */
> +#define FLEX_VERSION 0xfc/* Version Register */
> +
> +/* Mode Register bit fields */
> +#define FLEX_MR_OPMODE_OFFSET(0)  /* Operating Mode */
> +#define FLEX_MR_OPMODE_MASK  (0x3 << FLEX_MR_OPMODE_OFFSET)
> +#define FLEX_MR_OPMODE(opmode)   (((opmode) << FLEX_MR_OPMODE_OFFSET) &  
> \
> +  FLEX_MR_OPMODE_MASK)
> +
> +
> +static int atmel_flexcom_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct clk *clk;
> + struct resource *res;
> + void __iomem *base;
> + u32 opmode;
> + int err;
> +
> + err = of_property_read_u32(np, "atmel,flexcom-mode", &opmode);
> + if (err)
> + return err;
> +
> + if (opmode < ATMEL_FLEXCOM_MODE_USART ||
> + opmode > ATMEL_FLEXCOM_MODE_TWI)
> + return -EINVAL;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + err = clk_prepare_enable(clk

[PATCH linux-next v11 3/3] mfd: atmel-flexcom: add a driver for Atmel Flexible Serial Communication Unit

2015-09-28 Thread Cyrille Pitchen 
This driver supports the new Atmel Flexcom. The Flexcom is a wrapper which
integrates one SPI controller, one I2C controller and one USART. Only one
function can be enabled at a time. This driver selects the function once
for all, when the Flexcom is probed, according to the value of the new
"atmel,flexcom-mode" device tree property.

This driver has chosen to present the Flexcom to the system as a MFD so
the implementation is seamless for the existing Atmel SPI, I2C and USART
drivers.

Also the Flexcom embeds FIFOs: the latest patches of the SPI, I2C and
USART drivers take advantage of this new feature.

Signed-off-by: Cyrille Pitchen 
Acked-by: Boris Brezillon 
Acked-by: Alexandre Belloni 
Acked-by: Nicolas Ferre 
---
 drivers/mfd/Kconfig |  11 +
 drivers/mfd/Makefile|   1 +
 drivers/mfd/atmel-flexcom.c | 104 
 3 files changed, 116 insertions(+)
 create mode 100644 drivers/mfd/atmel-flexcom.c

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 99d63675f073..87e84e7c71da 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -60,6 +60,17 @@ config MFD_AAT2870_CORE
  additional drivers must be enabled in order to use the
  functionality of the device.
 
+config MFD_ATMEL_FLEXCOM
+   tristate "Atmel Flexcom (Flexible Serial Communication Unit)"
+   select MFD_CORE
+   depends on OF
+   help
+ Select this to get support for Atmel Flexcom. This is a wrapper
+ which embeds a SPI controller, a I2C controller and a USART. Only
+ one function can be used at a time. The choice is done at boot time
+ by the probe function of this MFD driver according to a device tree
+ property.
+
 config MFD_ATMEL_HLCDC
tristate "Atmel HLCDC (High-end LCD Controller)"
select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index d6c21e3c409f..a8b76b81b467 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -164,6 +164,7 @@ obj-$(CONFIG_MFD_SPMI_PMIC) += qcom-spmi-pmic.o
 obj-$(CONFIG_TPS65911_COMPARATOR)  += tps65911-comparator.o
 obj-$(CONFIG_MFD_TPS65090) += tps65090.o
 obj-$(CONFIG_MFD_AAT2870_CORE) += aat2870-core.o
+obj-$(CONFIG_MFD_ATMEL_FLEXCOM)+= atmel-flexcom.o
 obj-$(CONFIG_MFD_ATMEL_HLCDC)  += atmel-hlcdc.o
 obj-$(CONFIG_MFD_INTEL_LPSS)   += intel-lpss.o
 obj-$(CONFIG_MFD_INTEL_LPSS_PCI)   += intel-lpss-pci.o
diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
new file mode 100644
index ..e8e67be6b493
--- /dev/null
+++ b/drivers/mfd/atmel-flexcom.c
@@ -0,0 +1,104 @@
+/*
+ * Driver for Atmel Flexcom
+ *
+ * Copyright (C) 2015 Atmel Corporation
+ *
+ * Author: Cyrille Pitchen 
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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, see .
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/* I/O register offsets */
+#define FLEX_MR0x0 /* Mode Register */
+#define FLEX_VERSION   0xfc/* Version Register */
+
+/* Mode Register bit fields */
+#define FLEX_MR_OPMODE_OFFSET  (0)  /* Operating Mode */
+#define FLEX_MR_OPMODE_MASK(0x3 << FLEX_MR_OPMODE_OFFSET)
+#define FLEX_MR_OPMODE(opmode) (((opmode) << FLEX_MR_OPMODE_OFFSET) &  \
+FLEX_MR_OPMODE_MASK)
+
+
+static int atmel_flexcom_probe(struct platform_device *pdev)
+{
+   struct device_node *np = pdev->dev.of_node;
+   struct clk *clk;
+   struct resource *res;
+   void __iomem *base;
+   u32 opmode;
+   int err;
+
+   err = of_property_read_u32(np, "atmel,flexcom-mode", &opmode);
+   if (err)
+   return err;
+
+   if (opmode < ATMEL_FLEXCOM_MODE_USART ||
+   opmode > ATMEL_FLEXCOM_MODE_TWI)
+   return -EINVAL;
+
+   res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+   base = devm_ioremap_resource(&pdev->dev, res);
+   if (IS_ERR(base))
+   return PTR_ERR(base);
+
+   clk = devm_clk_get(&pdev->dev, NULL);
+   if (IS_ERR(clk))
+   return PTR_ERR(clk);
+
+   err = clk_prepare_enable(clk);
+   if (err)
+   return err;
+
+   /*
+* Set the Operating Mode in the Mode Register: only the selected device
+* is clocked. Hence, registers of the other serial devices remain
+* inaccessible and are read as zero. Also the external I/O