serial: icom: switch vague casts to container_of

In icom, there is an ICOM_PORT macro to perform upcasts from struct
uart_port to struct icom_port. It's not completely safe and it works
only because the first member of icom_port is uart_port. Nowadays, we
use container_of for such an upcast instead.

So introduce a helper (to_icom_port()) with container_of in it and
convert all the ICOM_PORT users to the new helper. Apart from the code
and type safety, it's also clear what icom_port (the variable) is.
Unlike with the old ICOM_PORT (the macro with the cast).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220421085808.24152-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/icom.c b/drivers/tty/serial/icom.c
index 142257809e377399b0c51c9ac613ee8a7f3f1d6e..42ba953c697ef19eeee13fa4737e16594139a998 100644 (file)
--- a/drivers/tty/serial/icom.c
+++ b/drivers/tty/serial/icom.c
@@ -47,9 +47,13 @@
 
 #define ICOM_DRIVER_NAME "icom"
 #define NR_PORTS              128
-#define ICOM_PORT ((struct icom_port *)port)
 #define to_icom_adapter(d) container_of(d, struct icom_adapter, kref)
 
+static inline struct icom_port *to_icom_port(struct uart_port *port)
+{
+       return container_of(port, struct icom_port, uart_port);
+}
+
 static const struct pci_device_id icom_pci_table[] = {
        {
                .vendor = PCI_VENDOR_ID_IBM,
@@ -616,16 +620,17 @@ unlock:
 
 static int icom_write(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned long data_count;
        unsigned char cmdReg;
        unsigned long offset;
        int temp_tail = port->state->xmit.tail;
 
-       trace(ICOM_PORT, "WRITE", 0);
+       trace(icom_port, "WRITE", 0);
 
-       if (cpu_to_le16(ICOM_PORT->statStg->xmit[0].flags) &
+       if (cpu_to_le16(icom_port->statStg->xmit[0].flags) &
            SA_FLAGS_READY_TO_XMIT) {
-               trace(ICOM_PORT, "WRITE_FULL", 0);
+               trace(icom_port, "WRITE_FULL", 0);
                return 0;
        }
 
@@ -633,7 +638,7 @@ static int icom_write(struct uart_port *port)
        while ((port->state->xmit.head != temp_tail) &&
               (data_count <= XMIT_BUFF_SZ)) {
 
-               ICOM_PORT->xmit_buf[data_count++] =
+               icom_port->xmit_buf[data_count++] =
                    port->state->xmit.buf[temp_tail];
 
                temp_tail++;
@@ -641,22 +646,22 @@ static int icom_write(struct uart_port *port)
        }
 
        if (data_count) {
-               ICOM_PORT->statStg->xmit[0].flags =
+               icom_port->statStg->xmit[0].flags =
                    cpu_to_le16(SA_FLAGS_READY_TO_XMIT);
-               ICOM_PORT->statStg->xmit[0].leLength =
+               icom_port->statStg->xmit[0].leLength =
                    cpu_to_le16(data_count);
                offset =
-                   (unsigned long) &ICOM_PORT->statStg->xmit[0] -
-                   (unsigned long) ICOM_PORT->statStg;
-               *ICOM_PORT->xmitRestart =
-                   cpu_to_le32(ICOM_PORT->statStg_pci + offset);
-               cmdReg = readb(&ICOM_PORT->dram->CmdReg);
+                   (unsigned long) &icom_port->statStg->xmit[0] -
+                   (unsigned long) icom_port->statStg;
+               *icom_port->xmitRestart =
+                   cpu_to_le32(icom_port->statStg_pci + offset);
+               cmdReg = readb(&icom_port->dram->CmdReg);
                writeb(cmdReg | CMD_XMIT_RCV_ENABLE,
-                      &ICOM_PORT->dram->CmdReg);
-               writeb(START_XMIT, &ICOM_PORT->dram->StartXmitCmd);
-               trace(ICOM_PORT, "WRITE_START", data_count);
+                      &icom_port->dram->CmdReg);
+               writeb(START_XMIT, &icom_port->dram->StartXmitCmd);
+               trace(icom_port, "WRITE_START", data_count);
                /* write flush */
-               readb(&ICOM_PORT->dram->StartXmitCmd);
+               readb(&icom_port->dram->StartXmitCmd);
        }
 
        return data_count;
@@ -924,11 +929,12 @@ static irqreturn_t icom_interrupt(int irq, void *dev_id)
  */
 static unsigned int icom_tx_empty(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        int ret;
        unsigned long flags;
 
        spin_lock_irqsave(&port->lock, flags);
-       if (cpu_to_le16(ICOM_PORT->statStg->xmit[0].flags) &
+       if (cpu_to_le16(icom_port->statStg->xmit[0].flags) &
            SA_FLAGS_READY_TO_XMIT)
                ret = TIOCSER_TEMT;
        else
@@ -940,38 +946,40 @@ static unsigned int icom_tx_empty(struct uart_port *port)
 
 static void icom_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char local_osr;
 
-       trace(ICOM_PORT, "SET_MODEM", 0);
-       local_osr = readb(&ICOM_PORT->dram->osr);
+       trace(icom_port, "SET_MODEM", 0);
+       local_osr = readb(&icom_port->dram->osr);
 
        if (mctrl & TIOCM_RTS) {
-               trace(ICOM_PORT, "RAISE_RTS", 0);
+               trace(icom_port, "RAISE_RTS", 0);
                local_osr |= ICOM_RTS;
        } else {
-               trace(ICOM_PORT, "LOWER_RTS", 0);
+               trace(icom_port, "LOWER_RTS", 0);
                local_osr &= ~ICOM_RTS;
        }
 
        if (mctrl & TIOCM_DTR) {
-               trace(ICOM_PORT, "RAISE_DTR", 0);
+               trace(icom_port, "RAISE_DTR", 0);
                local_osr |= ICOM_DTR;
        } else {
-               trace(ICOM_PORT, "LOWER_DTR", 0);
+               trace(icom_port, "LOWER_DTR", 0);
                local_osr &= ~ICOM_DTR;
        }
 
-       writeb(local_osr, &ICOM_PORT->dram->osr);
+       writeb(local_osr, &icom_port->dram->osr);
 }
 
 static unsigned int icom_get_mctrl(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char status;
        unsigned int result;
 
-       trace(ICOM_PORT, "GET_MODEM", 0);
+       trace(icom_port, "GET_MODEM", 0);
 
-       status = readb(&ICOM_PORT->dram->isr);
+       status = readb(&icom_port->dram->isr);
 
        result = ((status & ICOM_DCD) ? TIOCM_CAR : 0)
            | ((status & ICOM_RI) ? TIOCM_RNG : 0)
@@ -982,44 +990,47 @@ static unsigned int icom_get_mctrl(struct uart_port *port)
 
 static void icom_stop_tx(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char cmdReg;
 
-       trace(ICOM_PORT, "STOP", 0);
-       cmdReg = readb(&ICOM_PORT->dram->CmdReg);
-       writeb(cmdReg | CMD_HOLD_XMIT, &ICOM_PORT->dram->CmdReg);
+       trace(icom_port, "STOP", 0);
+       cmdReg = readb(&icom_port->dram->CmdReg);
+       writeb(cmdReg | CMD_HOLD_XMIT, &icom_port->dram->CmdReg);
 }
 
 static void icom_start_tx(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char cmdReg;
 
-       trace(ICOM_PORT, "START", 0);
-       cmdReg = readb(&ICOM_PORT->dram->CmdReg);
+       trace(icom_port, "START", 0);
+       cmdReg = readb(&icom_port->dram->CmdReg);
        if ((cmdReg & CMD_HOLD_XMIT) == CMD_HOLD_XMIT)
                writeb(cmdReg & ~CMD_HOLD_XMIT,
-                      &ICOM_PORT->dram->CmdReg);
+                      &icom_port->dram->CmdReg);
 
        icom_write(port);
 }
 
 static void icom_send_xchar(struct uart_port *port, char ch)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char xdata;
        int index;
        unsigned long flags;
 
-       trace(ICOM_PORT, "SEND_XCHAR", ch);
+       trace(icom_port, "SEND_XCHAR", ch);
 
        /* wait .1 sec to send char */
        for (index = 0; index < 10; index++) {
                spin_lock_irqsave(&port->lock, flags);
-               xdata = readb(&ICOM_PORT->dram->xchar);
+               xdata = readb(&icom_port->dram->xchar);
                if (xdata == 0x00) {
-                       trace(ICOM_PORT, "QUICK_WRITE", 0);
-                       writeb(ch, &ICOM_PORT->dram->xchar);
+                       trace(icom_port, "QUICK_WRITE", 0);
+                       writeb(ch, &icom_port->dram->xchar);
 
                        /* flush write operation */
-                       xdata = readb(&ICOM_PORT->dram->xchar);
+                       xdata = readb(&icom_port->dram->xchar);
                        spin_unlock_irqrestore(&port->lock, flags);
                        break;
                }
@@ -1030,38 +1041,41 @@ static void icom_send_xchar(struct uart_port *port, char ch)
 
 static void icom_stop_rx(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char cmdReg;
 
-       cmdReg = readb(&ICOM_PORT->dram->CmdReg);
-       writeb(cmdReg & ~CMD_RCV_ENABLE, &ICOM_PORT->dram->CmdReg);
+       cmdReg = readb(&icom_port->dram->CmdReg);
+       writeb(cmdReg & ~CMD_RCV_ENABLE, &icom_port->dram->CmdReg);
 }
 
 static void icom_break(struct uart_port *port, int break_state)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char cmdReg;
        unsigned long flags;
 
        spin_lock_irqsave(&port->lock, flags);
-       trace(ICOM_PORT, "BREAK", 0);
-       cmdReg = readb(&ICOM_PORT->dram->CmdReg);
+       trace(icom_port, "BREAK", 0);
+       cmdReg = readb(&icom_port->dram->CmdReg);
        if (break_state == -1) {
-               writeb(cmdReg | CMD_SND_BREAK, &ICOM_PORT->dram->CmdReg);
+               writeb(cmdReg | CMD_SND_BREAK, &icom_port->dram->CmdReg);
        } else {
-               writeb(cmdReg & ~CMD_SND_BREAK, &ICOM_PORT->dram->CmdReg);
+               writeb(cmdReg & ~CMD_SND_BREAK, &icom_port->dram->CmdReg);
        }
        spin_unlock_irqrestore(&port->lock, flags);
 }
 
 static int icom_open(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        int retval;
 
-       kref_get(&ICOM_PORT->adapter->kref);
-       retval = startup(ICOM_PORT);
+       kref_get(&icom_port->adapter->kref);
+       retval = startup(icom_port);
 
        if (retval) {
-               kref_put(&ICOM_PORT->adapter->kref, icom_kref_release);
-               trace(ICOM_PORT, "STARTUP_ERROR", 0);
+               kref_put(&icom_port->adapter->kref, icom_kref_release);
+               trace(icom_port, "STARTUP_ERROR", 0);
                return retval;
        }
 
@@ -1070,23 +1084,25 @@ static int icom_open(struct uart_port *port)
 
 static void icom_close(struct uart_port *port)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        unsigned char cmdReg;
 
-       trace(ICOM_PORT, "CLOSE", 0);
+       trace(icom_port, "CLOSE", 0);
 
        /* stop receiver */
-       cmdReg = readb(&ICOM_PORT->dram->CmdReg);
-       writeb(cmdReg & ~CMD_RCV_ENABLE, &ICOM_PORT->dram->CmdReg);
+       cmdReg = readb(&icom_port->dram->CmdReg);
+       writeb(cmdReg & ~CMD_RCV_ENABLE, &icom_port->dram->CmdReg);
 
-       shutdown(ICOM_PORT);
+       shutdown(icom_port);
 
-       kref_put(&ICOM_PORT->adapter->kref, icom_kref_release);
+       kref_put(&icom_port->adapter->kref, icom_kref_release);
 }
 
 static void icom_set_termios(struct uart_port *port,
                             struct ktermios *termios,
                             struct ktermios *old_termios)
 {
+       struct icom_port *icom_port = to_icom_port(port);
        int baud;
        unsigned cflag, iflag;
        char new_config2;
@@ -1098,7 +1114,7 @@ static void icom_set_termios(struct uart_port *port,
        unsigned long flags;
 
        spin_lock_irqsave(&port->lock, flags);
-       trace(ICOM_PORT, "CHANGE_SPEED", 0);
+       trace(icom_port, "CHANGE_SPEED", 0);
 
        cflag = termios->c_cflag;
        iflag = termios->c_iflag;
@@ -1129,12 +1145,12 @@ static void icom_set_termios(struct uart_port *port,
        if (cflag & PARENB) {
                /* parity bit enabled */
                new_config2 |= ICOM_ACFG_PARITY_ENAB;
-               trace(ICOM_PORT, "PARENB", 0);
+               trace(icom_port, "PARENB", 0);
        }
        if (cflag & PARODD) {
                /* odd parity */
                new_config2 |= ICOM_ACFG_PARITY_ODD;
-               trace(ICOM_PORT, "PARODD", 0);
+               trace(icom_port, "PARODD", 0);
        }
 
        /* Determine divisor based on baud rate */
@@ -1154,100 +1170,100 @@ static void icom_set_termios(struct uart_port *port,
        uart_update_timeout(port, cflag, baud);
 
        /* CTS flow control flag and modem status interrupts */
-       tmp_byte = readb(&(ICOM_PORT->dram->HDLCConfigReg));
+       tmp_byte = readb(&(icom_port->dram->HDLCConfigReg));
        if (cflag & CRTSCTS)
                tmp_byte |= HDLC_HDW_FLOW;
        else
                tmp_byte &= ~HDLC_HDW_FLOW;
-       writeb(tmp_byte, &(ICOM_PORT->dram->HDLCConfigReg));
+       writeb(tmp_byte, &(icom_port->dram->HDLCConfigReg));
 
        /*
         * Set up parity check flag
         */
-       ICOM_PORT->read_status_mask = SA_FLAGS_OVERRUN | SA_FL_RCV_DONE;
+       icom_port->read_status_mask = SA_FLAGS_OVERRUN | SA_FL_RCV_DONE;
        if (iflag & INPCK)
-               ICOM_PORT->read_status_mask |=
+               icom_port->read_status_mask |=
                    SA_FLAGS_FRAME_ERROR | SA_FLAGS_PARITY_ERROR;
 
        if ((iflag & BRKINT) || (iflag & PARMRK))
-               ICOM_PORT->read_status_mask |= SA_FLAGS_BREAK_DET;
+               icom_port->read_status_mask |= SA_FLAGS_BREAK_DET;
 
        /*
         * Characters to ignore
         */
-       ICOM_PORT->ignore_status_mask = 0;
+       icom_port->ignore_status_mask = 0;
        if (iflag & IGNPAR)
-               ICOM_PORT->ignore_status_mask |=
+               icom_port->ignore_status_mask |=
                    SA_FLAGS_PARITY_ERROR | SA_FLAGS_FRAME_ERROR;
        if (iflag & IGNBRK) {
-               ICOM_PORT->ignore_status_mask |= SA_FLAGS_BREAK_DET;
+               icom_port->ignore_status_mask |= SA_FLAGS_BREAK_DET;
                /*
                 * If we're ignore parity and break indicators, ignore
                 * overruns too.  (For real raw support).
                 */
                if (iflag & IGNPAR)
-                       ICOM_PORT->ignore_status_mask |= SA_FLAGS_OVERRUN;
+                       icom_port->ignore_status_mask |= SA_FLAGS_OVERRUN;
        }
 
        /*
         * !!! ignore all characters if CREAD is not set
         */
        if ((cflag & CREAD) == 0)
-               ICOM_PORT->ignore_status_mask |= SA_FL_RCV_DONE;
+               icom_port->ignore_status_mask |= SA_FL_RCV_DONE;
 
        /* Turn off Receiver to prepare for reset */
-       writeb(CMD_RCV_DISABLE, &ICOM_PORT->dram->CmdReg);
+       writeb(CMD_RCV_DISABLE, &icom_port->dram->CmdReg);
 
        for (index = 0; index < 10; index++) {
-               if (readb(&ICOM_PORT->dram->PrevCmdReg) == 0x00) {
+               if (readb(&icom_port->dram->PrevCmdReg) == 0x00) {
                        break;
                }
        }
 
        /* clear all current buffers of data */
        for (rcv_buff = 0; rcv_buff < NUM_RBUFFS; rcv_buff++) {
-               ICOM_PORT->statStg->rcv[rcv_buff].flags = 0;
-               ICOM_PORT->statStg->rcv[rcv_buff].leLength = 0;
-               ICOM_PORT->statStg->rcv[rcv_buff].WorkingLength =
+               icom_port->statStg->rcv[rcv_buff].flags = 0;
+               icom_port->statStg->rcv[rcv_buff].leLength = 0;
+               icom_port->statStg->rcv[rcv_buff].WorkingLength =
                    (unsigned short int) cpu_to_le16(RCV_BUFF_SZ);
        }
 
        for (xmit_buff = 0; xmit_buff < NUM_XBUFFS; xmit_buff++) {
-               ICOM_PORT->statStg->xmit[xmit_buff].flags = 0;
+               icom_port->statStg->xmit[xmit_buff].flags = 0;
        }
 
        /* activate changes and start xmit and receiver here */
        /* Enable the receiver */
-       writeb(new_config3, &(ICOM_PORT->dram->async_config3));
-       writeb(new_config2, &(ICOM_PORT->dram->async_config2));
-       tmp_byte = readb(&(ICOM_PORT->dram->HDLCConfigReg));
+       writeb(new_config3, &(icom_port->dram->async_config3));
+       writeb(new_config2, &(icom_port->dram->async_config2));
+       tmp_byte = readb(&(icom_port->dram->HDLCConfigReg));
        tmp_byte |= HDLC_PPP_PURE_ASYNC | HDLC_FF_FILL;
-       writeb(tmp_byte, &(ICOM_PORT->dram->HDLCConfigReg));
-       writeb(0x04, &(ICOM_PORT->dram->FlagFillIdleTimer));    /* 0.5 seconds */
-       writeb(0xFF, &(ICOM_PORT->dram->ier));  /* enable modem signal interrupts */
+       writeb(tmp_byte, &(icom_port->dram->HDLCConfigReg));
+       writeb(0x04, &(icom_port->dram->FlagFillIdleTimer));    /* 0.5 seconds */
+       writeb(0xFF, &(icom_port->dram->ier));  /* enable modem signal interrupts */
 
        /* reset processor */
-       writeb(CMD_RESTART, &ICOM_PORT->dram->CmdReg);
+       writeb(CMD_RESTART, &icom_port->dram->CmdReg);
 
        for (index = 0; index < 10; index++) {
-               if (readb(&ICOM_PORT->dram->CmdReg) == 0x00) {
+               if (readb(&icom_port->dram->CmdReg) == 0x00) {
                        break;
                }
        }
 
        /* Enable Transmitter and Receiver */
        offset =
-           (unsigned long) &ICOM_PORT->statStg->rcv[0] -
-           (unsigned long) ICOM_PORT->statStg;
-       writel(ICOM_PORT->statStg_pci + offset,
-              &ICOM_PORT->dram->RcvStatusAddr);
-       ICOM_PORT->next_rcv = 0;
-       ICOM_PORT->put_length = 0;
-       *ICOM_PORT->xmitRestart = 0;
-       writel(ICOM_PORT->xmitRestart_pci,
-              &ICOM_PORT->dram->XmitStatusAddr);
-       trace(ICOM_PORT, "XR_ENAB", 0);
-       writeb(CMD_XMIT_RCV_ENABLE, &ICOM_PORT->dram->CmdReg);
+           (unsigned long) &icom_port->statStg->rcv[0] -
+           (unsigned long) icom_port->statStg;
+       writel(icom_port->statStg_pci + offset,
+              &icom_port->dram->RcvStatusAddr);
+       icom_port->next_rcv = 0;
+       icom_port->put_length = 0;
+       *icom_port->xmitRestart = 0;
+       writel(icom_port->xmitRestart_pci,
+              &icom_port->dram->XmitStatusAddr);
+       trace(icom_port, "XR_ENAB", 0);
+       writeb(CMD_XMIT_RCV_ENABLE, &icom_port->dram->CmdReg);
 
        spin_unlock_irqrestore(&port->lock, flags);
 }