Re: [RFC][Patch] IBM Real-Time "SMI Free" mode driver

+ if (readb(rtl+RTL_STATE) != value) {
+ if (value == 1)
+ writeb(1, (rtl+RTL_CMD));
+ else
+ writeb(2, (rtl+RTL_CMD));

writeb( 1 + value , ... ) ??

+ rtl = ioremap(table_addr, RTL_TABLE_SIZE);
+
+ if (!rtl) {
+ ret = -ENOMEM;
+ goto err_out;

Would it be better to eliminate all the ioremap special test casing and
just remap it once at load time, or at least use a single function so the
tests/printks don't all get duplicated ? That would also eliminate the
fact you can get multiple mappings of the same thing if there are
multiple parallel users.

I note also there is no locking versus multiple accessors - eg when
writing the RTL_CMD registers


+ /*get the address for the RTL table from the EBDA */
+ ebda_addr = *(unsigned short *)phys_to_virt(0x40E);
+ ebda_addr <<= 4;
+ ebda_size = 64*1024;
+
+ data = ioremap(ebda_addr, ebda_size);

Careful - it is perfectly valid for a BIOS EBDA table to be zero
indicating no EBDA is present, and at this point you've not checked if
the driver is being loaded on a relevant IBM platform.

+ unsigned int *tmp = (unsigned int *) data++;

Use u32 - it makea it obvious what is going on here.

+/*needed to decode CmdPortAddress and CmdPortValue*/
+#define bios_to_value(rtl, offset) (u32)((readb(rtl+(offset+1)) << 8) + \
+ readb(rtl+offset))

What is wrong with readw() ?


Alan
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