diff options
Diffstat (limited to 'drivers/media/pci/netup_unidvb/netup_unidvb_i2c.c')
| -rw-r--r-- | drivers/media/pci/netup_unidvb/netup_unidvb_i2c.c | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/drivers/media/pci/netup_unidvb/netup_unidvb_i2c.c b/drivers/media/pci/netup_unidvb/netup_unidvb_i2c.c new file mode 100644 index 000000000..eaaa2d0a5 --- /dev/null +++ b/drivers/media/pci/netup_unidvb/netup_unidvb_i2c.c @@ -0,0 +1,381 @@ +/* + * netup_unidvb_i2c.c + * + * Internal I2C bus driver for NetUP Universal Dual DVB-CI + * + * Copyright (C) 2014 NetUP Inc. + * Copyright (C) 2014 Sergey Kozlov <serjk@netup.ru> + * Copyright (C) 2014 Abylay Ospan <aospan@netup.ru> + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/delay.h> +#include "netup_unidvb.h" + +#define NETUP_I2C_BUS0_ADDR 0x4800 +#define NETUP_I2C_BUS1_ADDR 0x4840 +#define NETUP_I2C_TIMEOUT 1000 + +/* twi_ctrl0_stat reg bits */ +#define TWI_IRQEN_COMPL 0x1 +#define TWI_IRQEN_ANACK 0x2 +#define TWI_IRQEN_DNACK 0x4 +#define TWI_IRQ_COMPL (TWI_IRQEN_COMPL << 8) +#define TWI_IRQ_ANACK (TWI_IRQEN_ANACK << 8) +#define TWI_IRQ_DNACK (TWI_IRQEN_DNACK << 8) +#define TWI_IRQ_TX 0x800 +#define TWI_IRQ_RX 0x1000 +#define TWI_IRQEN (TWI_IRQEN_COMPL | TWI_IRQEN_ANACK | TWI_IRQEN_DNACK) +/* twi_addr_ctrl1 reg bits*/ +#define TWI_TRANSFER 0x100 +#define TWI_NOSTOP 0x200 +#define TWI_SOFT_RESET 0x2000 +/* twi_clkdiv reg value */ +#define TWI_CLKDIV 156 +/* fifo_stat_ctrl reg bits */ +#define FIFO_IRQEN 0x8000 +#define FIFO_RESET 0x4000 +/* FIFO size */ +#define FIFO_SIZE 16 + +struct netup_i2c_fifo_regs { + union { + __u8 data8; + __le16 data16; + __le32 data32; + }; + __u8 padding[4]; + __le16 stat_ctrl; +} __packed __aligned(1); + +struct netup_i2c_regs { + __le16 clkdiv; + __le16 twi_ctrl0_stat; + __le16 twi_addr_ctrl1; + __le16 length; + __u8 padding1[8]; + struct netup_i2c_fifo_regs tx_fifo; + __u8 padding2[6]; + struct netup_i2c_fifo_regs rx_fifo; +} __packed __aligned(1); + +irqreturn_t netup_i2c_interrupt(struct netup_i2c *i2c) +{ + u16 reg, tmp; + unsigned long flags; + irqreturn_t iret = IRQ_HANDLED; + + spin_lock_irqsave(&i2c->lock, flags); + reg = readw(&i2c->regs->twi_ctrl0_stat); + writew(reg & ~TWI_IRQEN, &i2c->regs->twi_ctrl0_stat); + dev_dbg(i2c->adap.dev.parent, + "%s(): twi_ctrl0_state 0x%x\n", __func__, reg); + if ((reg & TWI_IRQEN_COMPL) != 0 && (reg & TWI_IRQ_COMPL)) { + dev_dbg(i2c->adap.dev.parent, + "%s(): TWI_IRQEN_COMPL\n", __func__); + i2c->state = STATE_DONE; + goto irq_ok; + } + if ((reg & TWI_IRQEN_ANACK) != 0 && (reg & TWI_IRQ_ANACK)) { + dev_dbg(i2c->adap.dev.parent, + "%s(): TWI_IRQEN_ANACK\n", __func__); + i2c->state = STATE_ERROR; + goto irq_ok; + } + if ((reg & TWI_IRQEN_DNACK) != 0 && (reg & TWI_IRQ_DNACK)) { + dev_dbg(i2c->adap.dev.parent, + "%s(): TWI_IRQEN_DNACK\n", __func__); + i2c->state = STATE_ERROR; + goto irq_ok; + } + if ((reg & TWI_IRQ_RX) != 0) { + tmp = readw(&i2c->regs->rx_fifo.stat_ctrl); + writew(tmp & ~FIFO_IRQEN, &i2c->regs->rx_fifo.stat_ctrl); + i2c->state = STATE_WANT_READ; + dev_dbg(i2c->adap.dev.parent, + "%s(): want read\n", __func__); + goto irq_ok; + } + if ((reg & TWI_IRQ_TX) != 0) { + tmp = readw(&i2c->regs->tx_fifo.stat_ctrl); + writew(tmp & ~FIFO_IRQEN, &i2c->regs->tx_fifo.stat_ctrl); + i2c->state = STATE_WANT_WRITE; + dev_dbg(i2c->adap.dev.parent, + "%s(): want write\n", __func__); + goto irq_ok; + } + dev_warn(&i2c->adap.dev, "%s(): not mine interrupt\n", __func__); + iret = IRQ_NONE; +irq_ok: + spin_unlock_irqrestore(&i2c->lock, flags); + if (iret == IRQ_HANDLED) + wake_up(&i2c->wq); + return iret; +} + +static void netup_i2c_reset(struct netup_i2c *i2c) +{ + dev_dbg(i2c->adap.dev.parent, "%s()\n", __func__); + i2c->state = STATE_DONE; + writew(TWI_SOFT_RESET, &i2c->regs->twi_addr_ctrl1); + writew(TWI_CLKDIV, &i2c->regs->clkdiv); + writew(FIFO_RESET, &i2c->regs->tx_fifo.stat_ctrl); + writew(FIFO_RESET, &i2c->regs->rx_fifo.stat_ctrl); + writew(0x800, &i2c->regs->tx_fifo.stat_ctrl); + writew(0x800, &i2c->regs->rx_fifo.stat_ctrl); +} + +static void netup_i2c_fifo_tx(struct netup_i2c *i2c) +{ + u8 data; + u32 fifo_space = FIFO_SIZE - + (readw(&i2c->regs->tx_fifo.stat_ctrl) & 0x3f); + u32 msg_length = i2c->msg->len - i2c->xmit_size; + + msg_length = (msg_length < fifo_space ? msg_length : fifo_space); + while (msg_length--) { + data = i2c->msg->buf[i2c->xmit_size++]; + writeb(data, &i2c->regs->tx_fifo.data8); + dev_dbg(i2c->adap.dev.parent, + "%s(): write 0x%02x\n", __func__, data); + } + if (i2c->xmit_size < i2c->msg->len) { + dev_dbg(i2c->adap.dev.parent, + "%s(): TX IRQ enabled\n", __func__); + writew(readw(&i2c->regs->tx_fifo.stat_ctrl) | FIFO_IRQEN, + &i2c->regs->tx_fifo.stat_ctrl); + } +} + +static void netup_i2c_fifo_rx(struct netup_i2c *i2c) +{ + u8 data; + u32 fifo_size = readw(&i2c->regs->rx_fifo.stat_ctrl) & 0x3f; + + dev_dbg(i2c->adap.dev.parent, + "%s(): RX fifo size %d\n", __func__, fifo_size); + while (fifo_size--) { + data = readb(&i2c->regs->rx_fifo.data8); + if ((i2c->msg->flags & I2C_M_RD) != 0 && + i2c->xmit_size < i2c->msg->len) { + i2c->msg->buf[i2c->xmit_size++] = data; + dev_dbg(i2c->adap.dev.parent, + "%s(): read 0x%02x\n", __func__, data); + } + } + if (i2c->xmit_size < i2c->msg->len) { + dev_dbg(i2c->adap.dev.parent, + "%s(): RX IRQ enabled\n", __func__); + writew(readw(&i2c->regs->rx_fifo.stat_ctrl) | FIFO_IRQEN, + &i2c->regs->rx_fifo.stat_ctrl); + } +} + +static void netup_i2c_start_xfer(struct netup_i2c *i2c) +{ + u16 rdflag = ((i2c->msg->flags & I2C_M_RD) ? 1 : 0); + u16 reg = readw(&i2c->regs->twi_ctrl0_stat); + + writew(TWI_IRQEN | reg, &i2c->regs->twi_ctrl0_stat); + writew(i2c->msg->len, &i2c->regs->length); + writew(TWI_TRANSFER | (i2c->msg->addr << 1) | rdflag, + &i2c->regs->twi_addr_ctrl1); + dev_dbg(i2c->adap.dev.parent, + "%s(): length %d twi_addr_ctrl1 0x%x twi_ctrl0_stat 0x%x\n", + __func__, readw(&i2c->regs->length), + readw(&i2c->regs->twi_addr_ctrl1), + readw(&i2c->regs->twi_ctrl0_stat)); + i2c->state = STATE_WAIT; + i2c->xmit_size = 0; + if (!rdflag) + netup_i2c_fifo_tx(i2c); + else + writew(FIFO_IRQEN | readw(&i2c->regs->rx_fifo.stat_ctrl), + &i2c->regs->rx_fifo.stat_ctrl); +} + +static int netup_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + unsigned long flags; + int i, trans_done, res = num; + struct netup_i2c *i2c = i2c_get_adapdata(adap); + u16 reg; + + if (num <= 0) { + dev_dbg(i2c->adap.dev.parent, + "%s(): num == %d\n", __func__, num); + return -EINVAL; + } + spin_lock_irqsave(&i2c->lock, flags); + if (i2c->state != STATE_DONE) { + dev_dbg(i2c->adap.dev.parent, + "%s(): i2c->state == %d, resetting I2C\n", + __func__, i2c->state); + netup_i2c_reset(i2c); + } + dev_dbg(i2c->adap.dev.parent, "%s() num %d\n", __func__, num); + for (i = 0; i < num; i++) { + i2c->msg = &msgs[i]; + netup_i2c_start_xfer(i2c); + trans_done = 0; + while (!trans_done) { + spin_unlock_irqrestore(&i2c->lock, flags); + if (wait_event_timeout(i2c->wq, + i2c->state != STATE_WAIT, + msecs_to_jiffies(NETUP_I2C_TIMEOUT))) { + spin_lock_irqsave(&i2c->lock, flags); + switch (i2c->state) { + case STATE_WANT_READ: + netup_i2c_fifo_rx(i2c); + break; + case STATE_WANT_WRITE: + netup_i2c_fifo_tx(i2c); + break; + case STATE_DONE: + if ((i2c->msg->flags & I2C_M_RD) != 0 && + i2c->xmit_size != i2c->msg->len) + netup_i2c_fifo_rx(i2c); + dev_dbg(i2c->adap.dev.parent, + "%s(): msg %d OK\n", + __func__, i); + trans_done = 1; + break; + case STATE_ERROR: + res = -EIO; + dev_dbg(i2c->adap.dev.parent, + "%s(): error state\n", + __func__); + goto done; + default: + dev_dbg(i2c->adap.dev.parent, + "%s(): invalid state %d\n", + __func__, i2c->state); + res = -EINVAL; + goto done; + } + if (!trans_done) { + i2c->state = STATE_WAIT; + reg = readw( + &i2c->regs->twi_ctrl0_stat); + writew(TWI_IRQEN | reg, + &i2c->regs->twi_ctrl0_stat); + } + spin_unlock_irqrestore(&i2c->lock, flags); + } else { + spin_lock_irqsave(&i2c->lock, flags); + dev_dbg(i2c->adap.dev.parent, + "%s(): wait timeout\n", __func__); + res = -ETIMEDOUT; + goto done; + } + spin_lock_irqsave(&i2c->lock, flags); + } + } +done: + spin_unlock_irqrestore(&i2c->lock, flags); + dev_dbg(i2c->adap.dev.parent, "%s(): result %d\n", __func__, res); + return res; +} + +static u32 netup_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm netup_i2c_algorithm = { + .master_xfer = netup_i2c_xfer, + .functionality = netup_i2c_func, +}; + +static struct i2c_adapter netup_i2c_adapter = { + .owner = THIS_MODULE, + .name = NETUP_UNIDVB_NAME, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &netup_i2c_algorithm, +}; + +static int netup_i2c_init(struct netup_unidvb_dev *ndev, int bus_num) +{ + int ret; + struct netup_i2c *i2c; + + if (bus_num < 0 || bus_num > 1) { + dev_err(&ndev->pci_dev->dev, + "%s(): invalid bus_num %d\n", __func__, bus_num); + return -EINVAL; + } + i2c = &ndev->i2c[bus_num]; + spin_lock_init(&i2c->lock); + init_waitqueue_head(&i2c->wq); + i2c->regs = (struct netup_i2c_regs *)(ndev->bmmio0 + + (bus_num == 0 ? NETUP_I2C_BUS0_ADDR : NETUP_I2C_BUS1_ADDR)); + netup_i2c_reset(i2c); + i2c->adap = netup_i2c_adapter; + i2c->adap.dev.parent = &ndev->pci_dev->dev; + i2c_set_adapdata(&i2c->adap, i2c); + ret = i2c_add_adapter(&i2c->adap); + if (ret) { + dev_err(&ndev->pci_dev->dev, + "%s(): failed to add I2C adapter\n", __func__); + return ret; + } + dev_info(&ndev->pci_dev->dev, + "%s(): registered I2C bus %d at 0x%x\n", + __func__, + bus_num, (bus_num == 0 ? + NETUP_I2C_BUS0_ADDR : + NETUP_I2C_BUS1_ADDR)); + return 0; +} + +static void netup_i2c_remove(struct netup_unidvb_dev *ndev, int bus_num) +{ + struct netup_i2c *i2c; + + if (bus_num < 0 || bus_num > 1) { + dev_err(&ndev->pci_dev->dev, + "%s(): invalid bus number %d\n", __func__, bus_num); + return; + } + i2c = &ndev->i2c[bus_num]; + netup_i2c_reset(i2c); + /* remove adapter */ + i2c_del_adapter(&i2c->adap); + dev_info(&ndev->pci_dev->dev, + "netup_i2c_remove: unregistered I2C bus %d\n", bus_num); +} + +int netup_i2c_register(struct netup_unidvb_dev *ndev) +{ + int ret; + + ret = netup_i2c_init(ndev, 0); + if (ret) + return ret; + ret = netup_i2c_init(ndev, 1); + if (ret) { + netup_i2c_remove(ndev, 0); + return ret; + } + return 0; +} + +void netup_i2c_unregister(struct netup_unidvb_dev *ndev) +{ + netup_i2c_remove(ndev, 0); + netup_i2c_remove(ndev, 1); +} + |