mxser: simplify mxser_interrupt and drop mxser_board::vector_mask

mxser_board::vector_mask is just a bitfield with bits set for all
available ports.  We can obtain this value simply by
"BIT(brd->info->nports) - 1" directly in the ISR. So remove vector_mask
and simplify the code a bit.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-15-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 555b9b37b52f312a0c5bfdaddb09a060a6d9b730..df59ca88acab8dc0adf5b326d29c5de84314b419 100644 (file)
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -368,7 +368,6 @@ struct mxser_board {
        int irq;
        const struct mxser_cardinfo *info;
        unsigned long vector;
-       unsigned long vector_mask;
 
        enum mxser_must_hwid must_hwid;
        speed_t max_baud;
@@ -2273,18 +2272,18 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
        struct mxser_board *brd = dev_id;
        struct mxser_port *port;
        unsigned int int_cnt, pass_counter = 0;
-       int max, irqbits, bits, i;
+       unsigned int i, max = brd->info->nports;
        int handled = IRQ_NONE;
+       u8 irqbits, bits, mask = BIT(max) - 1;
 
-       max = brd->info->nports;
        while (pass_counter++ < MXSER_ISR_PASS_LIMIT) {
-               irqbits = inb(brd->vector) & brd->vector_mask;
-               if (irqbits == brd->vector_mask)
+               irqbits = inb(brd->vector) & mask;
+               if (irqbits == mask)
                        break;
 
                handled = IRQ_HANDLED;
                for (i = 0, bits = 1; i < max; i++, irqbits |= bits, bits <<= 1) {
-                       if (irqbits == brd->vector_mask)
+                       if (irqbits == mask)
                                break;
                        if (bits & irqbits)
                                continue;
@@ -2450,7 +2449,6 @@ static int mxser_probe(struct pci_dev *pdev,
        brd->irq = pdev->irq;
 
        brd->must_hwid = mxser_must_get_hwid(brd->ports[0].ioaddr);
-       brd->vector_mask = 0;
 
        for (j = 0; j < UART_INFO_NUM; j++) {
                if (Gpci_uart_info[j].type == brd->must_hwid) {
@@ -2475,7 +2473,6 @@ static int mxser_probe(struct pci_dev *pdev,
        }
 
        for (i = 0; i < brd->info->nports; i++) {
-               brd->vector_mask |= (1 << i);
                brd->ports[i].baud_base = 921600;
        }