mtd: rawnand: Pass the CS line to be selected in struct nand_operation

In order to deprecate the ->select_chip hook we need to pass the CS
line a NAND operations are targeting. This is done through the
addition of a cs field to the nand_operation struct.

We also need to keep track of the currently selected target to
properly initialize op->cs, hence the ->cur_cs field addition to the
nand_chip struct.

Note that op->cs is not assigned in nand_exec_op() because we might
rework the way we execute NAND operations in the future (adopt a
queuing mechanism instead of the serialization we have right now).

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Tested-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
diff --git a/drivers/mtd/nand/raw/internals.h b/drivers/mtd/nand/raw/internals.h
index 6e2f61f..b62728d 100644
--- a/drivers/mtd/nand/raw/internals.h
+++ b/drivers/mtd/nand/raw/internals.h
@@ -101,6 +101,9 @@
 	if (!chip->exec_op)
 		return -ENOTSUPP;
 
+	if (WARN_ON(op->cs >= chip->numchips))
+		return -EINVAL;
+
 	return chip->exec_op(chip, op, false);
 }
 
diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index f85e6f3..7aa661f7 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -246,6 +246,7 @@
 	if (WARN_ON(cs > chip->numchips))
 		return;
 
+	chip->cur_cs = cs;
 	chip->select_chip(chip, cs);
 }
 EXPORT_SYMBOL_GPL(nand_select_target);
@@ -260,6 +261,7 @@
 void nand_deselect_target(struct nand_chip *chip)
 {
 	chip->select_chip(chip, -1);
+	chip->cur_cs = -1;
 }
 EXPORT_SYMBOL_GPL(nand_deselect_target);
 
@@ -1022,7 +1024,7 @@
 				 PSEC_TO_NSEC(sdr->tRR_min)),
 		NAND_OP_DATA_IN(len, buf, 0),
 	};
-	struct nand_operation op = NAND_OPERATION(instrs);
+	struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 	int ret;
 
 	/* Drop the DATA_IN instruction if len is set to 0. */
@@ -1065,7 +1067,7 @@
 				 PSEC_TO_NSEC(sdr->tRR_min)),
 		NAND_OP_DATA_IN(len, buf, 0),
 	};
-	struct nand_operation op = NAND_OPERATION(instrs);
+	struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 	int ret;
 
 	/* Drop the DATA_IN instruction if len is set to 0. */
@@ -1160,7 +1162,7 @@
 					 PSEC_TO_NSEC(sdr->tRR_min)),
 			NAND_OP_8BIT_DATA_IN(len, buf, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		/* Drop the DATA_IN instruction if len is set to 0. */
 		if (!len)
@@ -1216,7 +1218,7 @@
 				    PSEC_TO_NSEC(sdr->tCCS_min)),
 			NAND_OP_DATA_IN(len, buf, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 		int ret;
 
 		ret = nand_fill_column_cycles(chip, addrs, offset_in_page);
@@ -1298,7 +1300,7 @@
 		NAND_OP_CMD(NAND_CMD_PAGEPROG, PSEC_TO_NSEC(sdr->tWB_max)),
 		NAND_OP_WAIT_RDY(PSEC_TO_MSEC(sdr->tPROG_max), 0),
 	};
-	struct nand_operation op = NAND_OPERATION(instrs);
+	struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 	int naddrs = nand_fill_column_cycles(chip, addrs, offset_in_page);
 	int ret;
 	u8 status;
@@ -1412,7 +1414,7 @@
 				    PSEC_TO_NSEC(sdr->tWB_max)),
 			NAND_OP_WAIT_RDY(PSEC_TO_MSEC(sdr->tPROG_max), 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		ret = nand_exec_op(chip, &op);
 		if (ret)
@@ -1520,7 +1522,7 @@
 			NAND_OP_ADDR(2, addrs, PSEC_TO_NSEC(sdr->tCCS_min)),
 			NAND_OP_DATA_OUT(len, buf, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 		int ret;
 
 		ret = nand_fill_column_cycles(chip, addrs, offset_in_page);
@@ -1574,7 +1576,7 @@
 			NAND_OP_ADDR(1, &addr, PSEC_TO_NSEC(sdr->tADL_min)),
 			NAND_OP_8BIT_DATA_IN(len, buf, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		/* Drop the DATA_IN instruction if len is set to 0. */
 		if (!len)
@@ -1613,7 +1615,7 @@
 				    PSEC_TO_NSEC(sdr->tADL_min)),
 			NAND_OP_8BIT_DATA_IN(1, status, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		if (!status)
 			op.ninstrs--;
@@ -1646,7 +1648,7 @@
 		struct nand_op_instr instrs[] = {
 			NAND_OP_CMD(NAND_CMD_READ0, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
@@ -1685,7 +1687,7 @@
 				    PSEC_TO_MSEC(sdr->tWB_max)),
 			NAND_OP_WAIT_RDY(PSEC_TO_MSEC(sdr->tBERS_max), 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		if (chip->options & NAND_ROW_ADDR_3)
 			instrs[1].ctx.addr.naddrs++;
@@ -1743,7 +1745,7 @@
 					      PSEC_TO_NSEC(sdr->tWB_max)),
 			NAND_OP_WAIT_RDY(PSEC_TO_MSEC(sdr->tFEAT_max), 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
@@ -1791,7 +1793,7 @@
 			NAND_OP_8BIT_DATA_IN(ONFI_SUBFEATURE_PARAM_LEN,
 					     data, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
@@ -1811,7 +1813,7 @@
 			NAND_OP_WAIT_RDY(PSEC_TO_MSEC(timeout_ms),
 					 PSEC_TO_NSEC(delay_ns)),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
@@ -1844,7 +1846,7 @@
 			NAND_OP_CMD(NAND_CMD_RESET, PSEC_TO_NSEC(sdr->tWB_max)),
 			NAND_OP_WAIT_RDY(PSEC_TO_MSEC(sdr->tRST_max), 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
@@ -1878,7 +1880,7 @@
 		struct nand_op_instr instrs[] = {
 			NAND_OP_DATA_IN(len, buf, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		instrs[0].ctx.data.force_8bit = force_8bit;
 
@@ -1922,7 +1924,7 @@
 		struct nand_op_instr instrs[] = {
 			NAND_OP_DATA_OUT(len, buf, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		instrs[0].ctx.data.force_8bit = force_8bit;
 
@@ -5006,6 +5008,9 @@
 	unsigned int i;
 	int ret;
 
+	/* Assume all dies are deselected when we enter nand_scan_ident(). */
+	chip->cur_cs = -1;
+
 	/* Enforce the right timings for reset/detection */
 	onfi_fill_data_interface(chip, NAND_SDR_IFACE, 0);
 
diff --git a/drivers/mtd/nand/raw/nand_hynix.c b/drivers/mtd/nand/raw/nand_hynix.c
index ac1b5c1..1e4499d0 100644
--- a/drivers/mtd/nand/raw/nand_hynix.c
+++ b/drivers/mtd/nand/raw/nand_hynix.c
@@ -84,7 +84,7 @@
 		struct nand_op_instr instrs[] = {
 			NAND_OP_CMD(cmd, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
@@ -103,7 +103,7 @@
 			NAND_OP_ADDR(1, &addr, 0),
 			NAND_OP_8BIT_DATA_OUT(1, &val, 0),
 		};
-		struct nand_operation op = NAND_OPERATION(instrs);
+		struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
 
 		return nand_exec_op(chip, &op);
 	}
diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h
index def6dff..aa1512d 100644
--- a/include/linux/mtd/rawnand.h
+++ b/include/linux/mtd/rawnand.h
@@ -875,18 +875,21 @@
 
 /**
  * struct nand_operation - NAND operation descriptor
+ * @cs: the CS line to select for this NAND operation
  * @instrs: array of instructions to execute
  * @ninstrs: length of the @instrs array
  *
  * The actual operation structure that will be passed to chip->exec_op().
  */
 struct nand_operation {
+	unsigned int cs;
 	const struct nand_op_instr *instrs;
 	unsigned int ninstrs;
 };
 
-#define NAND_OPERATION(_instrs)					\
+#define NAND_OPERATION(_cs, _instrs)				\
 	{							\
+		.cs = _cs,					\
 		.instrs = _instrs,				\
 		.ninstrs = ARRAY_SIZE(_instrs),			\
 	}
@@ -1008,6 +1011,10 @@
  *			this nand device will encounter their life times.
  * @blocks_per_die:	[INTERN] The number of PEBs in a die
  * @data_interface:	[INTERN] NAND interface timing information
+ * @cur_cs:		currently selected target. -1 means no target selected,
+ *			otherwise we should always have cur_cs >= 0 &&
+ *			cur_cs < numchips. NAND Controller drivers should not
+ *			modify this value, but they're allowed to read it.
  * @read_retries:	[INTERN] the number of read retry modes supported
  * @setup_data_interface: [OPTIONAL] setup the data interface and timing. If
  *			  chipnr is set to %NAND_DATA_IFACE_CHECK_ONLY this
@@ -1069,6 +1076,8 @@
 
 	struct nand_data_interface data_interface;
 
+	int cur_cs;
+
 	int read_retries;
 
 	flstate_t state;