Re: [PATCH 2/2] m68k: add coldfire mcf5307 i2c support

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Greg,
thanks for the review,

On 05/10/2016 13:47, Greg Ungerer wrote:
Hi Angelo,

On 02/10/16 10:18, Angelo Dureghello wrote:
Add Steven King i2c driver for Coldfire, and reviewed to build
and run properly with the actual kernel version.

This won't be able to be merged in this form.
I can take the m68k/coldfire specific parts - but the i2c
driver would need to go via the i2c maintainers (so you
would need a patch to be sent and reveiwed on the i2c
email list).

I would prefer to merge the existing ColdFire i2c platform
support I have for all platforms in any case.


mainly, i can test things to work properly only on mcf5307,
even i f i am developing some other coldfire boards, they are not
still ready.
Ok i leave i2c/rtc entirely out for now. But i promise to work on it
step by step to have it accepted if board part is accepted,
so at least i have a starting point.

Regards
Greg



Best regards,
Angelo Dureghello


Signed-off-by: Angelo Dureghello <angelo@xxxxxxxx>
---
 arch/m68k/coldfire/device.c      | 191 ++++++++++++++++
 arch/m68k/coldfire/m5307.c       |  12 +
 arch/m68k/include/asm/m5307sim.h |   8 +
 arch/m68k/include/asm/mcfi2c.h   |  29 +++
 drivers/i2c/busses/Kconfig       |  12 +
 drivers/i2c/busses/Makefile      |   1 +
 drivers/i2c/busses/i2c-mcf.c     | 463 +++++++++++++++++++++++++++++++++++++++
 7 files changed, 716 insertions(+)
 create mode 100644 arch/m68k/include/asm/mcfi2c.h
 create mode 100644 drivers/i2c/busses/i2c-mcf.c

diff --git a/arch/m68k/coldfire/device.c b/arch/m68k/coldfire/device.c
index a0fc0c1..a1ed057 100644
--- a/arch/m68k/coldfire/device.c
+++ b/arch/m68k/coldfire/device.c
@@ -19,6 +19,7 @@
 #include <asm/mcfsim.h>
 #include <asm/mcfuart.h>
 #include <asm/mcfqspi.h>
+#include <asm/mcfi2c.h>

 /*
  *    All current ColdFire parts contain from 2, 3, 4 or 10 UARTS.
@@ -327,6 +328,178 @@ static struct platform_device mcf_qspi = {
 };
 #endif /* IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI) */

+#if IS_ENABLED(CONFIG_I2C_COLDFIRE)
+static struct resource mcf_i2c0_resources[] = {
+    {
+        .start          = MCFI2C_BASE0,
+        .end            = MCFI2C_BASE0 + MCFI2C_SIZE0 - 1,
+        .flags          = IORESOURCE_MEM,
+    },
+    {
+        .start          = MCF_IRQ_I2C0,
+        .end            = MCF_IRQ_I2C0,
+        .flags          = IORESOURCE_IRQ,
+    },
+};
+
+static struct mcfi2c_platform_data mcf_i2c0_platform_data = {
+    .bitrate                = 100000,
+};
+
+static struct platform_device mcf_i2c0 = {
+    .name                   = "mcfi2c",
+    .id                     = 0,
+    .num_resources          = ARRAY_SIZE(mcf_i2c0_resources),
+    .resource               = mcf_i2c0_resources,
+    .dev.platform_data      = &mcf_i2c0_platform_data,
+};
+#ifdef MCFI2C_BASE1
+
+static struct resource mcf_i2c1_resources[] = {
+    {
+        .start          = MCFI2C_BASE1,
+        .end            = MCFI2C_BASE1 + MCFI2C_SIZE1 - 1,
+        .flags          = IORESOURCE_MEM,
+    },
+    {
+        .start          = MCF_IRQ_I2C1,
+        .end            = MCF_IRQ_I2C1,
+        .flags          = IORESOURCE_IRQ,
+    },
+};
+
+static struct mcfi2c_platform_data mcf_i2c1_platform_data = {
+    .bitrate                = 100000,
+};
+
+static struct platform_device mcf_i2c1 = {
+    .name                   = "mcfi2c",
+    .id                     = 1,
+    .num_resources          = ARRAY_SIZE(mcf_i2c1_resources),
+    .resource               = mcf_i2c1_resources,
+    .dev.platform_data      = &mcf_i2c1_platform_data,
+};
+
+#endif /* MCFI2C_BASE1 */
+
+#ifdef MCFI2C_BASE2
+
+static struct resource mcf_i2c2_resources[] = {
+    {
+        .start          = MCFI2C_BASE2,
+        .end            = MCFI2C_BASE2 + MCFI2C_SIZE2 - 1,
+        .flags          = IORESOURCE_MEM,
+    },
+    {
+        .start          = MCF_IRQ_I2C2,
+        .end            = MCF_IRQ_I2C2,
+        .flags          = IORESOURCE_IRQ,
+    },
+};
+
+static struct mcfi2c_platform_data mcf_i2c2_platform_data = {
+    .bitrate                = 100000,
+};
+
+static struct platform_device mcf_i2c2 = {
+    .name                   = "mcfi2c",
+    .id                     = 2,
+    .num_resources          = ARRAY_SIZE(mcf_i2c2_resources),
+    .resource               = mcf_i2c2_resources,
+    .dev.platform_data      = &mcf_i2c2_platform_data,
+};
+
+#endif /* MCFI2C_BASE2 */
+
+#ifdef MCFI2C_BASE3
+
+static struct resource mcf_i2c3_resources[] = {
+    {
+        .start          = MCFI2C_BASE3,
+        .end            = MCFI2C_BASE3 + MCFI2C_SIZE3 - 1,
+        .flags          = IORESOURCE_MEM,
+    },
+    {
+        .start          = MCF_IRQ_I2C3,
+        .end            = MCF_IRQ_I2C3,
+        .flags          = IORESOURCE_IRQ,
+    },
+};
+
+static struct mcfi2c_platform_data mcf_i2c3_platform_data = {
+    .bitrate                = 100000,
+};
+
+static struct platform_device mcf_i2c3 = {
+    .name                   = "mcfi2c",
+    .id                     = 3,
+    .num_resources          = ARRAY_SIZE(mcf_i2c3_resources),
+    .resource               = mcf_i2c3_resources,
+    .dev.platform_data      = &mcf_i2c3_platform_data,
+};
+
+#endif /* MCFI2C_BASE3 */
+
+#ifdef MCFI2C_BASE4
+
+static struct resource mcf_i2c4_resources[] = {
+    {
+        .start          = MCFI2C_BASE4,
+        .end            = MCFI2C_BASE4 + MCFI2C_SIZE4 - 1,
+        .flags          = IORESOURCE_MEM,
+    },
+    {
+        .start          = MCF_IRQ_I2C4,
+        .end            = MCF_IRQ_I2C4,
+        .flags          = IORESOURCE_IRQ,
+    },
+};
+
+static struct mcfi2c_platform_data mcf_i2c4_platform_data = {
+    .bitrate                = 100000,
+};
+
+static struct platform_device mcf_i2c4 = {
+    .name                   = "mcfi2c",
+    .id                     = 4,
+    .num_resources          = ARRAY_SIZE(mcf_i2c4_resources),
+    .resource               = mcf_i2c4_resources,
+    .dev.platform_data      = &mcf_i2c4_platform_data,
+};
+
+#endif /* MCFI2C_BASE4 */
+
+#ifdef MCFI2C_BASE5
+
+static struct resource mcf_i2c5_resources[] = {
+    {
+        .start          = MCFI2C_BASE5,
+        .end            = MCFI2C_BASE5 + MCFI2C_SIZE5 - 1,
+        .flags          = IORESOURCE_MEM,
+    },
+    {
+        .start          = MCF_IRQ_I2C5,
+        .end            = MCF_IRQ_I2C5,
+        .flags          = IORESOURCE_IRQ,
+    },
+};
+
+static struct mcfi2c_platform_data mcf_i2c5_platform_data = {
+    .bitrate                = 100000,
+};
+
+static struct platform_device mcf_i2c5 = {
+    .name                   = "mcfi2c",
+    .id                     = 5,
+    .num_resources          = ARRAY_SIZE(mcf_i2c5_resources),
+    .resource               = mcf_i2c5_resources,
+    .dev.platform_data      = &mcf_i2c5_platform_data,
+};
+
+#endif /* MCFI2C_BASE5 */
+
+#endif /* IS_ENABLED(CONFIG_I2C_COLDFIRE) */
+
 static struct platform_device *mcf_devices[] __initdata = {
     &mcf_uart,
 #if IS_ENABLED(CONFIG_FEC)
@@ -338,6 +511,24 @@ static struct platform_device *mcf_devices[] __initdata = {
 #if IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI)
     &mcf_qspi,
 #endif
+#if IS_ENABLED(CONFIG_I2C_COLDFIRE)
+    &mcf_i2c0,
+#ifdef MCFI2C_BASE1
+    &mcf_i2c1,
+#endif
+#ifdef MCFI2C_BASE2
+    &mcf_i2c2,
+#endif
+#ifdef MCFI2C_BASE3
+    &mcf_i2c3,
+#endif
+#ifdef MCFI2C_BASE4
+    &mcf_i2c4,
+#endif
+#ifdef MCFI2C_BASE5
+    &mcf_i2c5,
+#endif
+#endif
 };

 /*
diff --git a/arch/m68k/coldfire/m5307.c b/arch/m68k/coldfire/m5307.c
index 2da1d14..159485e 100644
--- a/arch/m68k/coldfire/m5307.c
+++ b/arch/m68k/coldfire/m5307.c
@@ -35,6 +35,7 @@ DEFINE_CLK(mcftmr0, "mcftmr.0", MCF_BUSCLK);
 DEFINE_CLK(mcftmr1, "mcftmr.1", MCF_BUSCLK);
 DEFINE_CLK(mcfuart0, "mcfuart.0", MCF_BUSCLK);
 DEFINE_CLK(mcfuart1, "mcfuart.1", MCF_BUSCLK);
+DEFINE_CLK(mcfi2c0, "mcfi2c.0", MCF_BUSCLK);

 struct clk *mcf_clks[] = {
     &clk_pll,
@@ -43,9 +44,19 @@ struct clk *mcf_clks[] = {
     &clk_mcftmr1,
     &clk_mcfuart0,
     &clk_mcfuart1,
+    &clk_mcfi2c0,
     NULL
 };

+static void __init m5307_i2c_init(void)
+{
+#if IS_ENABLED(CONFIG_I2C_COLDFIRE)
+    writeb(MCFSIM_ICR_AUTOVEC | MCFSIM_ICR_LEVEL5 | MCFSIM_ICR_PRI0,
+           MCFSIM_I2CICR);
+    mcf_mapirq2imr(MCF_IRQ_I2C0, MCFINTC_I2C);
+#endif /* IS_ENABLED(CONFIG_I2C_COLDFIRE) */
+}
+
 /***************************************************************************/

 void __init config_BSP(char *commandp, int size)
@@ -73,6 +84,7 @@ void __init config_BSP(char *commandp, int size)
      */
     wdebug(MCFDEBUG_CSR, MCFDEBUG_CSR_PSTCLK);
 #endif
+    m5307_i2c_init();
 }

 /***************************************************************************/
diff --git a/arch/m68k/include/asm/m5307sim.h b/arch/m68k/include/asm/m5307sim.h
index 5d0bb7e..608e04c 100644
--- a/arch/m68k/include/asm/m5307sim.h
+++ b/arch/m68k/include/asm/m5307sim.h
@@ -131,6 +131,12 @@
 #define MCFGPIO_IRQ_MAX        -1
 #define MCFGPIO_IRQ_VECBASE    -1

+/*
+ * I2C module.
+ */
+#define MCFI2C_BASE0        (MCF_MBAR + 0x280)
+#define MCFI2C_SIZE0        0x40
+

 /* Definition offset address for CS2-7  -- old mask 5307 */

@@ -148,6 +154,7 @@
 #define    MCFSIM_SWDICR        MCFSIM_ICR0    /* Watchdog timer ICR */
 #define    MCFSIM_TIMER1ICR    MCFSIM_ICR1    /* Timer 1 ICR */
 #define    MCFSIM_TIMER2ICR    MCFSIM_ICR2    /* Timer 2 ICR */
+#define MCFSIM_I2CICR        MCFSIM_ICR3    /* I2C ICR */
 #define    MCFSIM_UART1ICR        MCFSIM_ICR4    /* UART 1 ICR */
 #define    MCFSIM_UART2ICR        MCFSIM_ICR5    /* UART 2 ICR */
 #define    MCFSIM_DMA0ICR        MCFSIM_ICR6    /* DMA 0 ICR */
@@ -174,6 +181,7 @@
 /*
  *    Define system peripheral IRQ usage.
  */
+#define MCF_IRQ_I2C0        29        /* I2C */
 #define    MCF_IRQ_TIMER        30        /* Timer0, Level 6 */
 #define    MCF_IRQ_PROFILER    31        /* Timer1, Level 7 */
 #define    MCF_IRQ_UART0        73        /* UART0 */
diff --git a/arch/m68k/include/asm/mcfi2c.h b/arch/m68k/include/asm/mcfi2c.h
new file mode 100644
index 0000000..a0c69e1
--- /dev/null
+++ b/arch/m68k/include/asm/mcfi2c.h
@@ -0,0 +1,29 @@
+/*
+ * Definitions for Coldfire I2C interface
+ */
+#ifndef mcfi2c_h
+#define mcfi2c_h
+
+#if defined(CONFIG_M5206) || defined(CONFIG_M5206e)
+#define MCFI2C_IOBASE  (MCF_MBAR + 0x1e0)
+#elif defined(CONFIG_M523x) || defined(CONFIG_M527x) || defined(CONFIG_M528x)
+#define MCFI2C_IOBASE  (MCF_IPSBAR + 0x300)
+#elif defined(CONFIG_M5249) || defined(CONFIG_M5307) || defined(CONFIG_M5407)
+#define MCFI2C_IOBASE  (MCF_MBAR + 0x280)
+#ifdef CONFIG_M5249
+#define MCFI2C_IOBASE2 (MCF_MBAR2 + 0x440)
+#endif
+#elif defined(CONFIG_M520x) || defined(CONFIG_M532x) || defined(CONFIG_M5445x)
+#define MCFI2C_IOBASE  0xFC058000
+#endif
+#define MCFI2C_IOSIZE   0x40
+
+/*
+ * struct mcfi2c_platform_data - platform data for the coldfire i2c driver
+ * @bitrate: bitrate to use for this i2c controller.
+ */
+struct mcfi2c_platform_data {
+    u32 bitrate;
+};
+
+#endif /* mcfi2c_h */
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 5c3993b..5c3e326 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -597,6 +597,18 @@ config I2C_IMX
       This driver can also be built as a module.  If so, the module
       will be called i2c-imx.

+config I2C_COLDFIRE
+    tristate "Freescale Coldfire I2C driver"
+    depends on M5206 || M5206e || M520x || M523x || M5249 || \
+           M527x || M528x || M5307 || M532x || M5407
+    help
+      This driver supports the I2C interface availible on some Freescale
+      Coldfire processors (M520x, M523x, M5249, M5271, M5275, M528x,
+      M5307, M532x, M5407).
+
+      This driver can be built as a module.  If so, the module
+      will be called i2c-mcf.
+
 config I2C_IOP3XX
     tristate "Intel IOPx3xx and IXP4xx on-chip I2C interface"
     depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IXP4XX || ARCH_IOP13XX
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 37f2819..17ad0c8 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -96,6 +96,7 @@ obj-$(CONFIG_I2C_XILINX)    += i2c-xiic.o
 obj-$(CONFIG_I2C_XLR)        += i2c-xlr.o
 obj-$(CONFIG_I2C_XLP9XX)    += i2c-xlp9xx.o
 obj-$(CONFIG_I2C_RCAR)        += i2c-rcar.o
+obj-$(CONFIG_I2C_COLDFIRE)      += i2c-mcf.o

 # External I2C/SMBus adapter drivers
 obj-$(CONFIG_I2C_DIOLAN_U2C)    += i2c-diolan-u2c.o
diff --git a/drivers/i2c/busses/i2c-mcf.c b/drivers/i2c/busses/i2c-mcf.c
new file mode 100644
index 0000000..320531c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-mcf.c
@@ -0,0 +1,463 @@
+/*
+ * Freescale/Motorola Coldfire I2C driver.
+ *
+ * Copyright 2010 Steven King <sfking@xxxxxxxxx>
+ *
+ * Updated by Angelo Dureghello <angelo@xxxxxxxx> Sep 2016
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+
+#include <asm/mcfi2c.h>
+
+#define DRIVER_NAME "mcfi2c"
+
+#define MCFI2C_ADR        0x00
+#define MCFI2C_FDR        0x04
+#define MCFI2C_CR        0x08
+#define    MCFI2C_CR_IEN        0x80
+#define    MCFI2C_CR_IIEN        0x40
+#define    MCFI2C_CR_MSTA        0x20
+#define    MCFI2C_CR_MTX        0x10
+#define    MCFI2C_CR_TXAK        0x08
+#define    MCFI2C_CR_RSTA        0x04
+#define MCFI2C_DR        0x10
+#define MCFI2C_SR        0x0C
+#define    MCFI2C_SR_ICF        0x80
+#define    MCFI2C_SR_IAAS        0x40
+#define    MCFI2C_SR_IBB        0x20
+#define    MCFI2C_SR_IAL        0x10
+#define    MCFI2C_SR_SRW        0x04
+#define    MCFI2C_SR_IIF        0x02
+#define    MCFI2C_SR_RXAK        0x01
+
+#define DEFAULT_I2C_BUS_SPEED    100000
+
+struct mcfi2c {
+    struct i2c_adapter      adapter;
+    void __iomem            *iobase;
+    int                     irq;
+    struct clk              *clk;
+    struct completion       completion;
+};
+
+static u8 mcfi2c_rd_cr(struct mcfi2c *mcfi2c)
+{
+    return readb(mcfi2c->iobase + MCFI2C_CR);
+}
+
+static void mcfi2c_wr_cr(struct mcfi2c *mcfi2c, u8 val)
+{
+    writeb(val, mcfi2c->iobase + MCFI2C_CR);
+}
+
+static u8 mcfi2c_rd_sr(struct mcfi2c *mcfi2c)
+{
+    return readb(mcfi2c->iobase + MCFI2C_SR);
+}
+
+static void mcfi2c_wr_sr(struct mcfi2c *mcfi2c, u8 val)
+{
+    writeb(val, mcfi2c->iobase + MCFI2C_SR);
+}
+
+static u8 mcfi2c_rd_dr(struct mcfi2c *mcfi2c)
+{
+    return readb(mcfi2c->iobase + MCFI2C_DR);
+}
+
+static void mcfi2c_wr_dr(struct mcfi2c *mcfi2c, u8 val)
+{
+    writeb(val, mcfi2c->iobase + MCFI2C_DR);
+}
+
+static void mcfi2c_start(struct mcfi2c *mcfi2c)
+{
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN | MCFI2C_CR_IIEN | MCFI2C_CR_MSTA |
+            MCFI2C_CR_MTX);
+}
+
+static void mcfi2c_repeat_start(struct mcfi2c *mcfi2c)
+{
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN | MCFI2C_CR_IIEN | MCFI2C_CR_MSTA |
+            MCFI2C_CR_MTX | MCFI2C_CR_RSTA);
+}
+
+static void mcfi2c_stop(struct mcfi2c *mcfi2c)
+{
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN);
+}
+
+static void mcfi2c_tx_ack(struct mcfi2c *mcfi2c)
+{
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN | MCFI2C_CR_IIEN | MCFI2C_CR_MSTA);
+}
+
+static void mcfi2c_tx_nak(struct mcfi2c *mcfi2c)
+{
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN | MCFI2C_CR_IIEN | MCFI2C_CR_MSTA |
+            MCFI2C_CR_TXAK);
+}
+
+static irqreturn_t mcfi2c_irq_handler(int this_irq, void *dev_id)
+{
+    struct mcfi2c *mcfi2c = dev_id;
+
+    /* clear interrupt */
+    mcfi2c_wr_sr(mcfi2c, 0);
+    complete(&mcfi2c->completion);
+
+    return IRQ_HANDLED;
+}
+
+static void mcfi2c_reset(struct mcfi2c *mcfi2c)
+{
+    mcfi2c_wr_cr(mcfi2c, 0);
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN | MCFI2C_CR_MSTA);
+    mcfi2c_rd_dr(mcfi2c);
+    mcfi2c_wr_sr(mcfi2c, 0);
+    mcfi2c_wr_cr(mcfi2c, 0);
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN);
+}
+
+static void mcfi2c_wait_for_bus_idle(struct mcfi2c *mcfi2c)
+{
+    if (mcfi2c_rd_sr(mcfi2c) & MCFI2C_SR_IBB) {
+        unsigned long timeout = jiffies + HZ / 2;
+
+        do {
+            cond_resched();
+            if (time_after(jiffies, timeout)) {
+                mcfi2c_reset(mcfi2c);
+                break;
+            }
+        } while (mcfi2c_rd_sr(mcfi2c) & MCFI2C_SR_IBB);
+    }
+}
+
+static int mcfi2c_wait_for_bus_busy(struct mcfi2c *mcfi2c)
+{
+    u8 sr;
+
+    while (!((sr = mcfi2c_rd_sr(mcfi2c)) & MCFI2C_SR_IBB))
+        if (sr & MCFI2C_SR_IAL) {
+            mcfi2c_reset(mcfi2c);
+            return -EIO;
+        }
+
+    return 0;
+}
+
+static int mcfi2c_xmit(struct mcfi2c *mcfi2c, u16 addr, u16 flags, u8 *buf,
+            u16 len, int timeout, int more)
+{
+    if (!(mcfi2c_rd_cr(mcfi2c) & MCFI2C_CR_MSTA)) {
+        mcfi2c_wait_for_bus_idle(mcfi2c);
+
+        reinit_completion(&mcfi2c->completion);
+        mcfi2c_start(mcfi2c);
+
+        if (mcfi2c_wait_for_bus_busy(mcfi2c))
+            return -EIO;
+    }
+
+    mcfi2c_wr_dr(mcfi2c, (addr << 1) | (flags & I2C_M_RD));
+
+    while (wait_for_completion_timeout(&mcfi2c->completion, timeout)) {
+        u8 sr = mcfi2c_rd_sr(mcfi2c);
+
+        if (sr & MCFI2C_SR_IAL) {
+            mcfi2c_wr_sr(mcfi2c, ~MCFI2C_SR_IAL);
+            return -EIO;
+        } else if (mcfi2c_rd_cr(mcfi2c) & MCFI2C_CR_MTX) {
+            if (sr & MCFI2C_SR_RXAK) {
+                mcfi2c_stop(mcfi2c);
+                return -EIO;
+            } else if (flags & I2C_M_RD) {
+                if (len > 1)
+                    mcfi2c_tx_ack(mcfi2c);
+                else
+                    mcfi2c_tx_nak(mcfi2c);
+                /* dummy read */
+                mcfi2c_rd_dr(mcfi2c);
+            } else if (len--) {
+                mcfi2c_wr_dr(mcfi2c, *buf++);
+            } else {
+                if (more)
+                    mcfi2c_repeat_start(mcfi2c);
+                else
+                    mcfi2c_stop(mcfi2c);
+                return 0;
+            }
+        } else if (--len) {
+            if (!(len > 1))
+                mcfi2c_tx_nak(mcfi2c);
+            *buf++ = mcfi2c_rd_dr(mcfi2c);
+        } else {
+            if (more)
+                mcfi2c_repeat_start(mcfi2c);
+            else
+                mcfi2c_stop(mcfi2c);
+            *buf++ = mcfi2c_rd_dr(mcfi2c);
+            return 0;
+        }
+    }
+
+    mcfi2c_stop(mcfi2c);
+
+    return -ETIMEDOUT;
+}
+
+static int mcfi2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
+            int num)
+{
+    struct mcfi2c *mcfi2c = i2c_get_adapdata(adapter);
+    int cnt = 0;
+    int status;
+    int retries;
+
+    while (num--) {
+        retries = adapter->retries;
+        if (msgs->flags & ~I2C_M_RD)
+            return -EINVAL;
+
+        do {
+            status = mcfi2c_xmit(mcfi2c, msgs->addr, msgs->flags,
+                        msgs->buf, msgs->len,
+                        adapter->timeout, num);
+        } while (status && retries--);
+
+        if (status)
+            return status;
+        ++cnt;
+        ++msgs;
+    }
+
+    return cnt;
+}
+
+static u32 mcfi2c_func(struct i2c_adapter *adapter)
+{
+    return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm mcfi2c_algo = {
+    .master_xfer    = mcfi2c_xfer,
+    .functionality  = mcfi2c_func,
+};
+
+static const u16 mcfi2c_fdr[] = {
+      28,   30,   34,   40,   44,   48,   56,   68,
+      80,   88,  104,  128,  144,  160,  192,  240,
+     288,  320,  384,  480,  576,  640,  768,  960,
+    1152, 1280, 1536, 1920, 2304, 2560, 3072, 3840,
+      20,   22,   24,   26,   28,   32,   36,   40,
+      48,   56,   64,   72,   80,   96,  112,  128,
+     160,  192,  224,  256,  320,  384,  448,  512,
+     640,  768,  896, 1024, 1280, 1536, 1792, 2048
+};
+
+static u8 mcfi2c_calc_fdr(struct mcfi2c *mcfi2c,
+                struct mcfi2c_platform_data *pdata)
+{
+    u32 bitrate = (pdata && pdata->bitrate) ?
+            pdata->bitrate : DEFAULT_I2C_BUS_SPEED;
+    int div = clk_get_rate(mcfi2c->clk)/bitrate;
+    int r = 0, i = 0;
+
+    do {
+        if (abs(mcfi2c_fdr[i] - div) < abs(mcfi2c_fdr[r] - div))
+            r = i;
+    } while (++i < ARRAY_SIZE(mcfi2c_fdr));
+
+    return r;
+}
+
+static int mcfi2c_probe(struct platform_device *pdev)
+{
+    struct mcfi2c *mcfi2c;
+    struct resource *res;
+    int status;
+
+    mcfi2c = kzalloc(sizeof(*mcfi2c), GFP_KERNEL);
+    if (!mcfi2c)
+        return -ENOMEM;
+
+    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+    if (!res) {
+        dev_dbg(&pdev->dev, "platform_get_resource failed\n");
+        status = -ENXIO;
+        goto fail0;
+    }
+
+    if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
+        dev_dbg(&pdev->dev, "request_mem_region failed\n");
+        status = -EBUSY;
+        goto fail0;
+    }
+
+    mcfi2c->iobase = ioremap(res->start, resource_size(res));
+    if (!mcfi2c->iobase) {
+        dev_dbg(&pdev->dev, "ioremap failed\n");
+        status = -ENOMEM;
+        goto fail1;
+    }
+
+    mcfi2c->irq = platform_get_irq(pdev, 0);
+    if (mcfi2c->irq < 0) {
+        dev_dbg(&pdev->dev, "platform_get_irq failed\n");
+        status = -ENXIO;
+        goto fail2;
+    }
+    status = request_irq(mcfi2c->irq, mcfi2c_irq_handler, 0,
+                pdev->name, mcfi2c);
+    if (status) {
+        dev_dbg(&pdev->dev, "request_irq failed\n");
+        goto fail2;
+    }
+
+    mcfi2c->clk = clk_get(&pdev->dev, "i2c_clk");
+    if (IS_ERR(mcfi2c->clk)) {
+        dev_dbg(&pdev->dev, "clk_get failed\n");
+        status = PTR_ERR(mcfi2c->clk);
+        goto fail3;
+    }
+    clk_enable(mcfi2c->clk);
+
+    platform_set_drvdata(pdev, mcfi2c);
+
+    init_completion(&mcfi2c->completion);
+
+    writeb(mcfi2c_calc_fdr(mcfi2c, pdev->dev.platform_data),
+        mcfi2c->iobase + MCFI2C_FDR);
+
+    writeb(0x00, mcfi2c->iobase + MCFI2C_ADR);
+
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN);
+
+    /* if the bus busy (IBB) is set, reset the controller */
+    if (mcfi2c_rd_sr(mcfi2c) & MCFI2C_SR_IBB)
+        mcfi2c_reset(mcfi2c);
+
+    mcfi2c->adapter.algo            = &mcfi2c_algo;
+    mcfi2c->adapter.class           = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+    mcfi2c->adapter.dev.parent      = &pdev->dev;
+    mcfi2c->adapter.nr              = pdev->id;
+    mcfi2c->adapter.retries         = 2;
+    snprintf(mcfi2c->adapter.name, sizeof(mcfi2c->adapter.name),
+            DRIVER_NAME ".%d", pdev->id);
+
+    i2c_set_adapdata(&mcfi2c->adapter, mcfi2c);
+
+    status = i2c_add_numbered_adapter(&mcfi2c->adapter);
+    if (status < 0) {
+        dev_dbg(&pdev->dev, "i2c_add_numbered_adapter failed\n");
+        goto fail4;
+    }
+    dev_info(&pdev->dev, "Coldfire I2C bus driver\n");
+
+    return 0;
+
+fail4:
+    clk_disable(mcfi2c->clk);
+    clk_put(mcfi2c->clk);
+fail3:
+    free_irq(mcfi2c->irq, mcfi2c);
+fail2:
+    iounmap(mcfi2c->iobase);
+fail1:
+    release_mem_region(res->start, resource_size(res));
+fail0:
+    kfree(mcfi2c);
+
+    return status;
+}
+
+static int mcfi2c_remove(struct platform_device *pdev)
+{
+    struct mcfi2c *mcfi2c = platform_get_drvdata(pdev);
+    struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+    /* disable the hardware */
+    mcfi2c_wr_cr(mcfi2c, 0);
+
+    platform_set_drvdata(pdev, NULL);
+    i2c_del_adapter(&mcfi2c->adapter);
+    clk_disable(mcfi2c->clk);
+    clk_put(mcfi2c->clk);
+    free_irq(mcfi2c->irq, mcfi2c);
+    iounmap(mcfi2c->iobase);
+    release_mem_region(res->start, resource_size(res));
+    kfree(mcfi2c);
+
+    return 0;
+}
+
+#ifdef CONFIG_PM
+static int mcfi2c_suspend(struct device *dev)
+{
+    struct mcfi2c *mcfi2c = platform_get_drvdata(to_platform_device(dev));
+
+    mcfi2c_wr_cr(mcfi2c, 0);
+    clk_disable(mcfi2c->clk);
+
+    return 0;
+}
+
+static int mcfi2c_resume(struct device *dev)
+{
+    struct mcfi2c *mcfi2c = platform_get_drvdata(to_platform_device(dev));
+
+    clk_enable(mcfi2c->clk);
+    mcfi2c_wr_cr(mcfi2c, MCFI2C_CR_IEN);
+
+    return 0;
+}
+
+static const struct dev_pm_ops mcfi2c_dev_pm_ops = {
+    .suspend        = mcfi2c_suspend,
+    .resume         = mcfi2c_resume,
+};
+
+#define MCFI2C_DEV_PM_OPS (&mcfi2c_dev_pm_ops)
+#else
+#define MCFI2C_DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver mcfi2c_driver = {
+    .driver.name    = DRIVER_NAME,
+    .driver.owner   = THIS_MODULE,
+    .driver.pm      = MCFI2C_DEV_PM_OPS,
+    .remove         = mcfi2c_remove,
+};
+
+static int __init mcfi2c_init(void)
+{
+    return platform_driver_probe(&mcfi2c_driver, mcfi2c_probe);
+}
+module_init(mcfi2c_init);
+
+static void __exit mcfi2c_exit(void)
+{
+    platform_driver_unregister(&mcfi2c_driver);
+}
+module_exit(mcfi2c_exit);
+
+MODULE_AUTHOR("Steven King <sfking@xxxxxxxxx>");
+MODULE_DESCRIPTION("I2C-Bus support for Freescale Coldfire processors");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);
+


--
To unsubscribe from this list: send the line "unsubscribe linux-m68k" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-m68k" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Video for Linux]     [Yosemite News]     [Linux S/390]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux