Hello Michał Mirosław, The patch 5f5bac8272be: "mmc: Driver for CB710/720 memory card reader (MMC part)" from May 22, 2009, leads to the following static checker warning: drivers/mmc/host/cb710-mmc.c:579 cb710_mmc_set_ios() warn: 'err' can be either negative or positive drivers/mmc/host/cb710-mmc.c 112 113 static int cb710_check_event(struct cb710_slot *slot, u8 what) 114 { 115 u16 status; 116 117 status = cb710_read_port_16(slot, CB710_MMC_STATUS_PORT); 118 119 if (status & CB710_MMC_S0_FIFO_UNDERFLOW) { 120 /* it is just a guess, so log it */ 121 dev_dbg(cb710_slot_dev(slot), 122 "CHECK : ignoring bit 6 in status %04X\n", status); 123 cb710_write_port_8(slot, CB710_MMC_STATUS0_PORT, 124 CB710_MMC_S0_FIFO_UNDERFLOW); 125 status &= ~CB710_MMC_S0_FIFO_UNDERFLOW; 126 } 127 128 if (status & CB710_MMC_STATUS_ERROR_EVENTS) { 129 dev_dbg(cb710_slot_dev(slot), 130 "CHECK : returning EIO on status %04X\n", status); 131 cb710_write_port_8(slot, CB710_MMC_STATUS0_PORT, status & 0xFF); 132 cb710_write_port_8(slot, CB710_MMC_STATUS1_PORT, 133 CB710_MMC_S1_RESET); 134 return -EIO; 135 } 136 137 /* 'what' is a bit in MMC_STATUS1 */ 138 if ((status >> 8) & what) { 139 cb710_write_port_8(slot, CB710_MMC_STATUS1_PORT, what); 140 return 1; There are two callers to this function. It appears to me that one expects zero on error and one expects non-zero on error. It is confusing and there are no comments explaining the return codes. 141 } 142 143 return 0; 144 } regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html