Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934148AbcJGPVn (ORCPT ); Fri, 7 Oct 2016 11:21:43 -0400 Received: from mail-wm0-f42.google.com ([74.125.82.42]:38830 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757162AbcJGPVF (ORCPT ); Fri, 7 Oct 2016 11:21:05 -0400 From: Pantelis Antoniou To: Lee Jones Cc: Linus Walleij , Alexandre Courbot , Rob Herring , Mark Rutland , Frank Rowand , Wolfram Sang , David Woodhouse , Brian Norris , Florian Fainelli , Wim Van Sebroeck , Peter Rosin , Debjit Ghosh , Georgi Vlaev , Guenter Roeck , Maryam Seraj , Pantelis Antoniou , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, linux-i2c@vger.kernel.org, linux-mtd@lists.infradead.org, linux-watchdog@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 03/10] i2c: Juniper SAM I2C driver Date: Fri, 7 Oct 2016 18:18:31 +0300 Message-Id: <1475853518-22264-4-git-send-email-pantelis.antoniou@konsulko.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1475853518-22264-1-git-send-email-pantelis.antoniou@konsulko.com> References: <1475853518-22264-1-git-send-email-pantelis.antoniou@konsulko.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 27108 Lines: 1003 From: Maryam Seraj Introduce SAM I2C driver for the I2C interfaces on the Juniper SAM FPGA. Signed-off-by: Maryam Seraj Signed-off-by: Debjit Ghosh Signed-off-by: Georgi Vlaev Signed-off-by: Guenter Roeck Signed-off-by: Rajat Jain [Ported from Juniper kernel] Signed-off-by: Pantelis Antoniou --- drivers/i2c/busses/Kconfig | 11 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-sam.c | 942 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 954 insertions(+) create mode 100644 drivers/i2c/busses/i2c-sam.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 5c3993b..eeac4b2 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -833,6 +833,17 @@ config I2C_SH7760 This driver can also be built as a module. If so, the module will be called i2c-sh7760. +config I2C_SAM + tristate "Juniper SAM FPGA I2C Controller" + select I2C_MUX + depends on MFD_JUNIPER_SAM || MFD_JUNIPER_CBC + help + This driver supports the I2C interfaces on the Juniper SAM FPGA + which is present on the relevant Juniper platforms. + + This driver can also be built as a module. If so, the module + will be called i2c-sam. + config I2C_SH_MOBILE tristate "SuperH Mobile I2C Controller" depends on HAS_DMA diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 37f2819..b99b229 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -79,6 +79,7 @@ obj-$(CONFIG_I2C_QUP) += i2c-qup.o obj-$(CONFIG_I2C_RIIC) += i2c-riic.o obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o +obj-$(CONFIG_I2C_SAM) += i2c-sam.o obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o obj-$(CONFIG_I2C_SH_MOBILE) += i2c-sh_mobile.o obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o diff --git a/drivers/i2c/busses/i2c-sam.c b/drivers/i2c/busses/i2c-sam.c new file mode 100644 index 0000000..1ec930a --- /dev/null +++ b/drivers/i2c/busses/i2c-sam.c @@ -0,0 +1,942 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define SAM_DEB1(dev, fmt, args...) do { \ + if (sam_debug >= 1) \ + dev_err(dev, fmt, ## args); \ + } while (0) +#define SAM_DEB2(dev, fmt, args...) do { \ + if (sam_debug >= 2) \ + dev_err(dev, fmt, ## args); \ + } while (0) +#define SAM_DEB3(dev, fmt, args...) do { \ + if (sam_debug >= 3) \ + dev_err(dev, fmt, ## args); } \ + while (0) + +static int sam_debug; + +#define DRIVER_DESC "SAM FPGA I2C Driver" +#define DRIVER_VERSION "0.2" +#define DRIVER_AUTHOR "Maryam Seraj " + +#define SAM_FPGA_MODULE_NAME "i2c-sam" + +#define SAM_I2C_MUX_MAX_CHAN 8 + +#define SAM_I2C_DEV_ADDR_MASK 0x7f +#define SAM_I2C_TBL_ENTRY_CMDS_NUM 2 + +#define SAM_I2C_CMD_TABLE_SZ 256 + +#define SAM_I2C_STS_DONE (1 << 0) +#define SAM_I2C_STS_PRIO_DONE (1 << 1) +#define SAM_I2C_STS_RUNNING (1 << 2) +#define SAM_I2C_STS_PRIO_RUNNING (1 << 3) +#define SAM_I2C_STS_ERR (1 << 4) +#define SAM_I2C_STS_PRIO_ERR (1 << 5) +#define SAM_I2C_STS_RDY (1 << 6) +#define SAM_I2C_STS_TR_TIMEOUT (1 << 7) +#define SAM_I2C_STS_CMD_TIMEOUT (1 << 8) +#define SAM_I2C_STS_CMD_TABLE_TIMEOUT (1 << 9) + +#define SAM_I2C_STS_CLEAR_MASK (SAM_I2C_STS_DONE \ + | SAM_I2C_STS_PRIO_DONE \ + | SAM_I2C_STS_TR_TIMEOUT \ + | SAM_I2C_STS_CMD_TIMEOUT \ + | SAM_I2C_STS_CMD_TABLE_TIMEOUT \ + | SAM_I2C_STS_ERR \ + | SAM_I2C_STS_PRIO_ERR) +#define SAM_I2C_STS_CLEAR(x) (((x) & ~0x3fb3) | SAM_I2C_STS_CLEAR_MASK) + +#define SAM_I2C_STS_TIMEOUT (SAM_I2C_STS_TR_TIMEOUT \ + | SAM_I2C_STS_CMD_TIMEOUT \ + | SAM_I2C_STS_CMD_TABLE_TIMEOUT) + +#define SAM_I2C_DONE(s) ((s) & (SAM_I2C_STS_DONE | SAM_I2C_STS_ERR \ + | SAM_I2C_STS_TIMEOUT)) + +#define SAM_I2C_CTRL_RESET (1 << 0) +#define SAM_I2C_CTRL_GO (1 << 1) +#define SAM_I2C_CTRL_PRIO_GO (1 << 2) +#define SAM_I2C_CTRL_ABORT (1 << 3) +#define SAM_I2C_CTRL_PRIO_ABORT (1 << 4) + +/* Priority ctrl & status bits are offset +1 from the regular */ +#define STS_DONE(p) BIT(0 + (p)) +#define STS_RUNNING(p) BIT(2 + (p)) +#define STS_ERR(p) BIT(4 + (p)) +#define CTRL_GO(p) BIT(1 + (p)) +#define CTRL_ABORT(p) BIT(3 + (p)) +#define STS_I2C_DONE(s, p) ((s) & (STS_DONE(p) | STS_ERR(p) \ + | SAM_I2C_STS_TIMEOUT)) + +struct sam_i2c_data { + void __iomem *membase; + void __iomem *masterbase; + int first_master; + int num_master; + int mux_channels; + u32 *speed; /* bit mask, 1 for high speed */ + bool prio; + bool reverse_fill; + struct i2c_adapter **adap; + struct device *dev; + int irq; + struct sam_platform_data *pdata; +}; + +struct sam_i2c_adapdata { + void __iomem *membase; + void __iomem *masterbase; + int channel; + int mux_channels; + int mux_select; + u32 speed; /* bit mask, same as above */ + int prio; + bool reverse_fill; + struct i2c_adapter adap; + struct i2c_mux_core *muxc; + wait_queue_head_t wait; + u32 status; + u32 control; + bool done; + bool polling; +}; + +/**************************** i2c stuff *****************************/ + +#define SAM_FPGA_MUX_NAME "sam-fpga-mux" + +enum i2c_accel_cmd_bits_s { + I2C_WRITE, /* 000 */ + I2C_READ, /* 001 */ + I2C_WRITE_STOP, /* 010 */ + I2C_READ_STOP, /* 011 */ + I2C_WRITE_REPSTART, /* 100 */ + I2C_READ_REPSTART /* 101 */ +}; + +#define I2C_CMD_STOP_BIT (1 << 1) +#define I2C_CMD_REPSTART_BIT (1 << 2) + +#define PER_MASTER_MEM 0x1000 +#define I2C_OPTIONS_BASE 0x2000 +#define MASTER_MEM_BASE 0x8000 + +#define CMD_ADDR(s, idx) ((s)->masterbase + 0x0000 + \ + PER_MASTER_MEM * (s)->channel + \ + (idx) * sizeof(u32)) +#define RES_ADDR(s, idx) ((s)->masterbase + 0x0400 + \ + PER_MASTER_MEM * (s)->channel + \ + (idx) * sizeof(u32)) +#define CMD_PRI_ADDR(s, idx) ((s)->masterbase + 0x0800 + \ + PER_MASTER_MEM * (s)->channel + \ + (idx) * sizeof(u32)) +#define RES_PRI_ADDR(s, idx) ((s)->masterbase + 0x0c00 + \ + PER_MASTER_MEM * (s)->channel + \ + (idx) * sizeof(u32)) +#define CTRL_ADDR(s) ((s)->membase + 0x2400 + 8 * (s)->channel) +#define STAT_ADDR(s) ((s)->membase + 0x2404 + 8 * (s)->channel) + +#define sam_i2c_stat_clear(adata, val) \ + do { \ + iowrite32(SAM_I2C_STS_CLEAR(val), STAT_ADDR(adata)); \ + ioread32(STAT_ADDR(adata)); \ + } while (0) + +static int sam_i2c_wait_rdy(struct i2c_adapter *adap) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + u32 val; + unsigned long timeout; + + val = ioread32(STAT_ADDR(adata)); + if ((val & SAM_I2C_STS_RDY) && !(val & STS_RUNNING(adata->prio))) + return 0; + + if (val & STS_RUNNING(adata->prio)) { + iowrite32(adata->control | CTRL_ABORT(adata->prio), + CTRL_ADDR(adata)); + ioread32(CTRL_ADDR(adata)); + udelay(10); + iowrite32(adata->control, CTRL_ADDR(adata)); + ioread32(CTRL_ADDR(adata)); + udelay(100); + } + + timeout = jiffies + adap->timeout; + adata->status = 0; + do { + val = ioread32(STAT_ADDR(adata)) | adata->status; + if ((val & SAM_I2C_STS_RDY) && + !(val & STS_RUNNING(adata->prio))) + return 0; + + if (adata->polling) { + udelay(50); + } else { + adata->done = false; + adata->status = 0; + wait_event_timeout(adata->wait, adata->done, + adap->timeout); + } + + } while (time_before(jiffies, timeout)); + + return -EBUSY; +} + +int sam_i2c_calc_start_entry(struct i2c_msg *msgs, int num, int reverse_fill) +{ + int i, len = 0; + + /* Filling the table from start (offset 0) ? */ + if (!reverse_fill) + return 0; + + /* Calculate required table size from the message sizes */ + if (num == 1 && msgs[0].len == 0) + len = 1; + else + for (i = 0; i < num; i++) + if (msgs[i].flags & I2C_M_RECV_LEN) + len += (I2C_SMBUS_BLOCK_MAX + 1); + else + len += msgs[i].len; + + if (len > SAM_I2C_CMD_TABLE_SZ * 2) + return -E2BIG; + + /* Always start from Command 0 */ + return (SAM_I2C_CMD_TABLE_SZ * 2 - len) / 2; +} + +static int sam_i2c_cmd_init(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + struct device *dev = &adap->dev; + struct i2c_msg *msg; + int curmsg, cmds = 0; + int addr, i, len = 0, table_offset = 0; + u32 cmd_entry; + bool read; + u8 group; + u32 idx; + u8 cmd; + + group = adata->mux_select; + addr = msgs[0].addr & SAM_I2C_DEV_ADDR_MASK; + cmd_entry = (group << 29) | (addr << 22); + + /* Zero CMD table */ + memset_io(CMD_ADDR(adata, 0), 0, SAM_I2C_CMD_TABLE_SZ * sizeof(u32)); + + idx = sam_i2c_calc_start_entry(msgs, num, adata->reverse_fill); + if (idx < 0) + return idx; + + table_offset = idx; + + for (curmsg = 0; curmsg < num; curmsg++) { + msg = &msgs[curmsg]; + read = msg->flags & I2C_M_RD; + + SAM_DEB1(dev, " [%02d] %s %d bytes addr %#02x\n", + curmsg, read ? "RD" : "WR", + msg->len, addr); + + len = msg->len; + if (len == 0 && curmsg == 0 && num == 1) { + /* + * SMBus quick command, special case + * + * Always read; we don't want to risk that + * a "WRITE_STOP" command as only command + * would actually write anything into the chip. + */ + cmd = I2C_READ_STOP; + cmd_entry |= cmd << 19; + cmds = 1; + break; + } + /* + * If the message is a SMBus block read message, read up to the + * maximum block length. The command should succeed at least up + * to the real block length, which will be returned in the first + * data byte. + */ + if (read && (msg->flags & I2C_M_RECV_LEN)) + len = I2C_SMBUS_BLOCK_MAX + 1; + for (i = 0; i < len; i++) { + cmd = read ? I2C_READ : I2C_WRITE; + if (i == len - 1) { + if (curmsg == num - 1) + cmd |= I2C_CMD_STOP_BIT; + else + cmd |= I2C_CMD_REPSTART_BIT; + } + + if ((cmds % SAM_I2C_TBL_ENTRY_CMDS_NUM) == 0) { + /* cmd0/data0 */ + cmd_entry |= cmd << 19; + if (!read) + cmd_entry |= (msg->buf[i] << 11); + } else { + /* cmd1/data1 */ + cmd_entry |= cmd << 8; + if (!read) + cmd_entry |= msg->buf[i]; + } + cmds++; + if (cmds % SAM_I2C_TBL_ENTRY_CMDS_NUM == 0) { + /* + * One command entry is done! + * Write it to the command table and start + * putting together the next entry for + * the same current i2c command, if needed. + */ + SAM_DEB2(dev, + "reg-offset cmd_entry = 0x%08x, cmds = %d, @ %p\n", + cmd_entry, cmds, CMD_ADDR(adata, idx)); + + iowrite32(cmd_entry, CMD_ADDR(adata, idx)); + ioread32(CMD_ADDR(adata, idx)); + idx++; + + /* clean out everything but group and address */ + cmd_entry &= 0xFFC00000; + } + } + } + /* + * Zero out any remaining cmd/data part of the last + * command entry into the command table of the given + * master before kicking off the i2c engine for this + * master. + */ + if (cmds % SAM_I2C_TBL_ENTRY_CMDS_NUM != 0) { + cmd_entry &= 0xFFFFF800; + + SAM_DEB1(dev, "rest of cmd_entry = 0x%08x, cmds = %d, @ %p\n", + cmd_entry, cmds, CMD_ADDR(adata, idx)); + + if (idx >= SAM_I2C_CMD_TABLE_SZ) + return -E2BIG; + + iowrite32(cmd_entry, CMD_ADDR(adata, idx)); + ioread32(CMD_ADDR(adata, idx)); + idx++; + if (idx < SAM_I2C_CMD_TABLE_SZ) { + iowrite32(0, CMD_ADDR(adata, idx)); + ioread32(CMD_ADDR(adata, idx)); + } + } + return table_offset; +} + +static u32 i2c_sam_wait_results(struct i2c_adapter *adap) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + struct device *dev = &adap->dev; + u32 val; + + if (adata->polling) { + unsigned long timeout = jiffies + adap->timeout; + + /* + * Poll for results. + * Only wait a short time per loop to avoid long access times. + * At 100kHz, a single byte transfer takes about 100 uS, + * so we don't want to wait much longer than that. + */ + do { + /* + * We should really use usleep_range() here, but that + * does not work and causes the system to lock up. + * msleep() is slow, so use an active wait loop instead. + */ + udelay(50); + val = ioread32(STAT_ADDR(adata)); + SAM_DEB1(dev, "status = 0x%08x @%p\n", + val, STAT_ADDR(adata)); + if (STS_I2C_DONE(val, adata->prio)) + break; + } while (time_before(jiffies, timeout)); + } else { + if (!wait_event_timeout(adata->wait, adata->done, + adap->timeout)) + val = ioread32(STAT_ADDR(adata)); + else + val = ioread32(STAT_ADDR(adata)) | adata->status; + } + + sam_i2c_stat_clear(adata, val); + + return val; +} + +static int sam_i2c_read_data(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num, int table_offset) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + int offset = table_offset * 2; + struct device *dev = &adap->dev; + struct i2c_msg *msg; + u32 val, data; + bool valid; + int i, len; + + msg = &msgs[num - 1]; + len = msg->len; + + if (num > 1) + offset += msgs[0].len; + + SAM_DEB1(dev, "Reading %d bytes\n", len); + + for (i = offset & 0xfffffffe; i < len + offset; i++) { + val = ioread32(RES_ADDR(adata, i / 2)); + SAM_DEB2(dev, "data = 0x%08x @%p\n", + val, RES_ADDR(adata, i / 2)); + if (i >= offset) { + data = (val >> 11) & 0xff; /* data_0 */ + valid = val & 0x00200000; /* valid_0 */ + if (!valid) + return -EIO; + msg->buf[i - offset] = data; + if (i == offset && + (msg->flags & I2C_M_RECV_LEN)) { + if (data == 0 || + data > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + SAM_DEB1(dev, "SMBus block data, %d bytes\n", + data); + len += data; + } + } + if (++i >= len + offset) + break; + if (i >= offset) { + data = val & 0xff; /* data_1 */ + valid = val & 0x00000400; /* valid_1 */ + if (!valid) + return -EIO; + msg->buf[i - offset] = data; + if (i == offset && + (msg->flags & I2C_M_RECV_LEN)) { + if (data == 0 || + data > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + SAM_DEB1(dev, "SMBus block data, %d bytes\n", + data); + len += data; + } + } + } + + return 0; +} + +static int sam_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + int ret, table_offset; + u32 val; + + ret = sam_i2c_wait_rdy(adap); + if (ret < 0) + return ret; + + ret = sam_i2c_cmd_init(adap, msgs, num); + if (ret < 0) + return ret; + table_offset = ret & 0xff; + + sam_i2c_stat_clear(adata, ioread32(STAT_ADDR(adata))); + + /* + * Done with setting up the command table, now kick + * off this transaction before waiting for the results. + */ + + adata->done = false; + adata->status = 0; + + iowrite32(adata->control | CTRL_GO(adata->prio) | table_offset << 24, + CTRL_ADDR(adata)); + ioread32(CTRL_ADDR(adata)); /* read back to flush */ + + val = i2c_sam_wait_results(adap); + if (val & STS_ERR(adata->prio)) { + dev_err(&adap->dev, "i2c transaction error\n"); + return -EIO; + } + if ((val & SAM_I2C_STS_TIMEOUT) || !(val & STS_DONE(adata->prio))) { + SAM_DEB1(&adap->dev, + "i2c transaction timeout, status=0x%x\n", val); + return -ETIMEDOUT; + } + + SAM_DEB1(&adap->dev, "i2c transaction completed!!!\n"); + + /* SMBus quick command, special case */ + if (num == 1 && msgs[0].len == 0) { + val = ioread32(RES_ADDR(adata, table_offset)); + SAM_DEB1(&adap->dev, "quick cmd: data = 0x%08x\n", val); + return val & 0x00200000 ? 1 : -EIO; + } + /* + * If this was a "read" request, go get the data. + * Otherwise, we're done here! + */ + if (msgs[num - 1].flags & I2C_M_RD) { + ret = sam_i2c_read_data(adap, msgs, num, table_offset); + if (ret < 0) + return ret; + } + + SAM_DEB1(&adap->dev, "Returning %d\n", num); + return num; +} + +static u32 sam_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA; +} + +static const struct i2c_algorithm sam_i2c_algo = { + .master_xfer = sam_i2c_xfer, + .functionality = sam_i2c_func, +}; + +/* + * This is where the SAM I2C-accel needs to be initialized. + */ +static int sam_i2c_init_adap(struct i2c_adapter *adap) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + u32 val; + + SAM_DEB1(&adap->dev, "bus_mstr = %d\n", adata->channel); + + val = 0x00000f00; + val |= (adata->speed << 12) & 0x0000f000; + adata->control = val; + /* + * Set the i2c speed for ALL ports of this master and enable them all + */ + iowrite32(val, CTRL_ADDR(adata)); + + return 0; +} + +int sam_i2c_add_numbered_bus(struct i2c_adapter *adap) +{ + int rval; + + SAM_DEB1(&adap->dev, "%s", __func__); + + rval = sam_i2c_init_adap(adap); + if (rval) + return rval; + + return i2c_add_numbered_adapter(adap); +} +/********** end of i2c adapter/accel stuff ************************************/ + +/********** start of i2c accel mux/group stuff ********************************/ +static int sam_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan) +{ + struct sam_i2c_adapdata *adata = i2c_mux_priv(muxc); + + if (!adata) + return -ENODEV; + adata->mux_select = chan; + + return 0; +} + +static int sam_i2c_mux_init(struct i2c_adapter *adap) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + int chan, ret; + + SAM_DEB1(&adap->dev, "%s Begin\n", __func__); + + adata->muxc = i2c_mux_alloc(adap, &adap->dev, adata->mux_channels, 0, 0, + sam_i2c_mux_select, NULL); + if (!adata->muxc) + return -ENOMEM; + adata->muxc->priv = adata; + + for (chan = 0; chan < adata->mux_channels; chan++) { + ret = i2c_mux_add_adapter(adata->muxc, 0, chan, 0); + if (ret) { + dev_err(&adap->dev, "Failed to add adapter %d\n", chan); + i2c_mux_del_adapters(adata->muxc); + return ret; + } + } + + SAM_DEB1(&adap->dev, "%s End\n", __func__); + + return 0; +} + +/********** end of i2c accel mux/group stuff **********************************/ + +static void sam_core_of_init_options(struct device *dev, + struct sam_i2c_data *sam) +{ + const __be32 *opt; + int len, i; + + opt = of_get_property(dev->of_node, "i2c-options", &len); + if (!opt || len > 4 * sizeof(u32)) + return; + + for (i = 0; i < len; i += sizeof(u32)) + iowrite32(be32_to_cpup(opt++), + sam->membase + I2C_OPTIONS_BASE + i); +} + +static int sam_core_of_init(struct device *dev, struct sam_i2c_data *sam, + struct resource *res) +{ + int err; + int num_master, max_masters; + u32 speed, mux_channels, val, master_offset = MASTER_MEM_BASE; + int i, len; + const __be32 *bus_range, *regs; + struct device_node *child; + u32 master, mux; + + num_master = ioread32(sam->membase + 0x0c); + sam->first_master = -1; + + err = of_property_read_u32(dev->of_node, "master-offset", &val); + if (!err) + if (val + PER_MASTER_MEM <= resource_size(res)) { + master_offset = val; + dev_info(dev, "Master offset changed to 0x%08x", val); + } + + sam->masterbase = sam->membase + master_offset; + max_masters = (resource_size(res) - master_offset) / PER_MASTER_MEM; + + if (num_master <= 0 || num_master > max_masters) + return -EINVAL; + sam->num_master = num_master; + + bus_range = of_get_property(dev->of_node, "i2c-bus-range", &len); + if (bus_range) { + if (len != 2 * sizeof(u32)) + return -EINVAL; + sam->first_master = be32_to_cpu(bus_range[0]); + num_master = be32_to_cpu(bus_range[1]) - sam->first_master + 1; + if (num_master <= 0 || num_master > sam->num_master) + return -EINVAL; + sam->num_master = num_master; + } + + sam->speed = devm_kcalloc(dev, sam->num_master, sizeof(u32), + GFP_KERNEL); + if (!sam->speed) + return -ENOMEM; + + sam->adap = devm_kcalloc(dev, sam->num_master, + sizeof(struct i2c_adapter *), GFP_KERNEL); + if (!sam->adap) + return -ENOMEM; + + /* Set default i2c speed to 100kHz for all channels */ + for (i = 0; i < sam->num_master; i++) + sam->speed[i] = (1 << SAM_I2C_MUX_MAX_CHAN) - 1; + + if (!dev->of_node) { + /* + * Use default from platform data if the there is no FDT. + * TODO: Use FDT once it is available + */ + sam->mux_channels = sam->pdata ? + sam->pdata->i2c_mux_channels : 2; + dev_warn(dev, + "No FDT node for SAM, using default (%d)\n", + sam->mux_channels); + return 0; + } + + err = of_property_read_u32(dev->of_node, "mux-channels", &mux_channels); + if (err || !mux_channels || mux_channels > SAM_I2C_MUX_MAX_CHAN) + return -EINVAL; + sam->mux_channels = mux_channels; + sam->reverse_fill = of_property_read_bool(dev->of_node, "reverse-fill"); + sam->prio = of_property_read_bool(dev->of_node, "priority-tables"); + /* Priority tables are offset with 0x800 from the regular tables */ + if (sam->prio) + sam->masterbase += 0x800; + + for_each_child_of_node(dev->of_node, child) { + regs = of_get_property(child, "reg", &len); + if (!regs || len != 2 * sizeof(u32)) { + dev_err(dev, "did not find reg property or bad size\n"); + return -EINVAL; + } + err = of_property_read_u32(child, "speed", &speed); + if (err || !speed) + continue; + if (speed != 100000 && speed != 400000) { + dev_err(dev, "Bad speed %d\n", speed); + return -EINVAL; + } + master = be32_to_cpu(regs[0]); + mux = be32_to_cpu(regs[1]); + if (master >= sam->num_master || mux >= sam->mux_channels) { + dev_err(dev, + "master/mux %d/%d out of range\n", + master, mux); + return -EINVAL; + } + if (speed == 400000) + sam->speed[master] &= ~(1 << mux); + } + + sam_core_of_init_options(dev, sam); + + return 0; +} + +static struct i2c_adapter *sam_i2c_init_one(struct sam_i2c_data *sam, + int channel) +{ + struct device *dev = sam->dev; + struct sam_i2c_adapdata *adata; + int err; + + adata = devm_kzalloc(dev, sizeof(*adata), GFP_KERNEL); + if (!adata) + return ERR_PTR(-ENOMEM); + + init_waitqueue_head(&adata->wait); + adata->adap.owner = THIS_MODULE; + adata->adap.algo = &sam_i2c_algo; + adata->adap.nr = (sam->first_master >= 0) ? + sam->first_master + channel : -1; + adata->adap.timeout = HZ / 5; + adata->channel = channel; + adata->mux_channels = sam->mux_channels; + adata->membase = sam->membase; + adata->masterbase = sam->masterbase; + adata->speed = sam->speed[channel]; + adata->polling = (sam->irq < 0); + adata->reverse_fill = sam->reverse_fill; + adata->prio = sam->prio & 1; + i2c_set_adapdata(&adata->adap, adata); + snprintf(adata->adap.name, sizeof(adata->adap.name), + "%s:%d", dev_name(dev), channel); + + adata->adap.dev.parent = dev; + err = sam_i2c_add_numbered_bus(&adata->adap); + if (err) + goto error; + + err = sam_i2c_mux_init(&adata->adap); + if (err) + goto err_remove; + + return &adata->adap; + +err_remove: + i2c_del_adapter(&adata->adap); +error: + return ERR_PTR(err); +} + +static void sam_i2c_cleanup_one(struct i2c_adapter *adap) +{ + struct sam_i2c_adapdata *adata = i2c_get_adapdata(adap); + + i2c_mux_del_adapters(adata->muxc); + i2c_del_adapter(adap); +} + +static irqreturn_t sam_i2c_irq_handler(int irq, void *data) +{ + struct sam_i2c_data *sam = data; + struct sam_platform_data *pdata = sam->pdata; + struct sam_i2c_adapdata *adata; + int bit; + u32 val, status, wake_status; + u32 mask = (1 << sam->num_master) - 1; + + status = pdata->irq_status(sam->dev->parent, SAM_IRQ_I2C, + sam->irq) & mask; + do { + wake_status = status; + /* Clear the 'done' bits */ + while (status) { + bit = __ffs(status); + status &= ~BIT(bit); + adata = i2c_get_adapdata(sam->adap[bit]); + val = ioread32(STAT_ADDR(adata)); + if (STS_I2C_DONE(val, adata->prio)) { + sam_i2c_stat_clear(adata, val); + if (!adata->done) { + adata->done = true; + adata->status = val; + } + } + } + /* + * Clear the status bits *after* the done status is cleared, + * as otherwise this will generate another unused interrupt. + * On the CBC this will also clear the MSI INT_ACCELL. + */ + pdata->irq_status_clear(sam->dev->parent, SAM_IRQ_I2C, sam->irq, + wake_status); + + /* Now wake the blocked transactions */ + while (wake_status) { + bit = __ffs(wake_status); + wake_status &= ~BIT(bit); + adata = i2c_get_adapdata(sam->adap[bit]); + wake_up(&adata->wait); + } + + /* Recheck the status again, as we might miss an MSI in + * the window from the last check and the clear of the + * pending interrupts. This does not affect the SAM INTx. + */ + status = pdata->irq_status(sam->dev->parent, SAM_IRQ_I2C, + sam->irq) & mask; + } while (status); + + return IRQ_HANDLED; +} + +static const struct of_device_id sam_i2c_of_match[] = { + { .compatible = "jnx,i2c-sam",}, + {}, +}; +MODULE_DEVICE_TABLE(of, sam_i2c_of_match); + + +static int sam_i2c_probe(struct platform_device *pdev) +{ + int err; + int i; + struct sam_i2c_data *sam; + struct i2c_adapter *adap; + struct resource *res; + struct device *dev = &pdev->dev; + struct sam_platform_data *pdata = dev_get_platdata(&pdev->dev); + + /* + * Allocate memory for the SAM FPGA info + */ + sam = devm_kzalloc(dev, sizeof(*sam), GFP_KERNEL); + if (!sam) + return -ENOMEM; + + platform_set_drvdata(pdev, sam); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + if (pdata) + sam->irq = platform_get_irq(pdev, 0); + + sam->membase = devm_ioremap_nocache(dev, res->start, + resource_size(res)); + if (!sam->membase) + return -ENOMEM; + + sam->dev = dev; + sam->pdata = pdata; + + err = sam_core_of_init(dev, sam, res); + if (err) + return err; + + /***** i2c init *****/ + + for (i = 0; i < sam->num_master; i++) { + adap = sam_i2c_init_one(sam, i); + if (IS_ERR(adap)) { + err = PTR_ERR(adap); + dev_err(dev, + "Failed to initialize adapter %d [base %d, index %d]: %d\n", + sam->first_master + i, sam->first_master, i, + err); + goto err_remove; + } + sam->adap[i] = adap; + } + + if (sam->irq >= 0) { + err = devm_request_any_context_irq(dev, sam->irq, + sam_i2c_irq_handler, 0, + dev_name(dev), sam); + if (err < 0) { + dev_err(dev, "Failed to request interrupt %d: %d\n", + sam->irq, err); + goto err_remove; + } + pdata->enable_irq(dev->parent, SAM_IRQ_I2C, sam->irq, + (1 << sam->num_master) - 1); + } + + return 0; + +err_remove: + for (i--; i >= 0; i--) + sam_i2c_cleanup_one(sam->adap[i]); + return err; +} + +static int sam_i2c_remove(struct platform_device *pdev) +{ + struct sam_i2c_data *sam = platform_get_drvdata(pdev); + struct sam_platform_data *pdata = sam->pdata; + int i; + + if (sam->irq >= 0 && pdata) + pdata->disable_irq(pdev->dev.parent, SAM_IRQ_I2C, sam->irq, + (1 << sam->num_master) - 1); + for (i = 0; i < sam->num_master; i++) + sam_i2c_cleanup_one(sam->adap[i]); + + return 0; +} + +static struct platform_driver sam_i2c_driver = { + .driver = { + .name = "i2c-sam", + .owner = THIS_MODULE, + .of_match_table = sam_i2c_of_match, + }, + .probe = sam_i2c_probe, + .remove = sam_i2c_remove, +}; + +module_platform_driver(sam_i2c_driver); + +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_VERSION(DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR(DRIVER_AUTHOR); + +module_param(sam_debug, int, S_IWUSR | S_IRUGO); -- 1.9.1