From b1c4b4d45263241ec6c2405a8df8265d4b58e707 Mon Sep 17 00:00:00 2001 From: Tristram Ha Date: Fri, 21 Jun 2024 15:34:22 -0700 Subject: [PATCH] net: dsa: microchip: fix wrong register write when masking interrupt The switch global port interrupt mask, REG_SW_PORT_INT_MASK__4, is defined as 0x001C in ksz9477_reg.h. The designers used 32-bit value in anticipation for increase of port count in future product but currently the maximum port count is 7 and the effective value is 0x7F in register 0x001F. Each port has its own interrupt mask and is defined as 0x#01F. It uses only 4 bits for different interrupts. The developer who implemented the current interrupt mechanism in the switch driver noticed there are similarities between the mechanism to mask port interrupts in global interrupt and individual interrupts in each port and so used the same code to handle these interrupts. He updated the code to use the new macro REG_SW_PORT_INT_MASK__1 which is defined as 0x1F in ksz_common.h but he forgot to update the 32-bit write to 8-bit as now the mask registers are 0x1F and 0x#01F. In addition all KSZ switches other than the KSZ9897/KSZ9893 and LAN937X families use only 8-bit access and so this common code will eventually be changed to accommodate them. Fixes: e1add7dd6183 ("net: dsa: microchip: use common irq routines for girq and pirq") Signed-off-by: Tristram Ha Link: https://lore.kernel.org/r/1719009262-2948-1-git-send-email-Tristram.Ha@microchip.com Signed-off-by: Paolo Abeni --- drivers/net/dsa/microchip/ksz_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 0433109b42e570..0580b2fee21c38 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -2196,7 +2196,7 @@ static void ksz_irq_bus_sync_unlock(struct irq_data *d) struct ksz_device *dev = kirq->dev; int ret; - ret = ksz_write32(dev, kirq->reg_mask, kirq->masked); + ret = ksz_write8(dev, kirq->reg_mask, kirq->masked); if (ret) dev_err(dev->dev, "failed to change IRQ mask\n");