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x86_64-suse-linux-gnu) Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Authentication-Results: smtp-out2.suse.de; none X-Spam-Level: X-Spam-Score: -4.10 X-Spamd-Result: default: False [-4.10 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; BAYES_HAM(-0.00)[33.78%]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_LONG(-3.00)[-1.000]; HAS_ORG_HEADER(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; TO_DN_ALL(0.00)[]; NEURAL_HAM_SHORT(-1.00)[-1.000]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_CC(0.00)[gmail.com,kernel.org]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[] I originally restricted i2c_register_spd() to only support systems with up to 4 memory slots, so that we can experiment with it on a limited numbers of systems. It's been more than 3 years and it seems to work just fine, so the time has come to lift this arbitrary limitation. The maximum number of memory slots which can be connected to a single I2C segment is 8, so support that many SPD EEPROMs. Any system with more than 8 memory slots would have either multiple SMBus channels or SMBus multiplexing, so it would need dedicated care. We'll get to that later as needed. Signed-off-by: Jean Delvare Cc: Heiner Kallweit Cc: Wolfram Sang --- drivers/i2c/i2c-smbus.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- linux-6.6.orig/drivers/i2c/i2c-smbus.c +++ linux-6.6/drivers/i2c/i2c-smbus.c @@ -308,8 +308,8 @@ EXPORT_SYMBOL_GPL(i2c_free_slave_host_no * target systems are the same. * Restrictions to automatic SPD instantiation: * - Only works if all filled slots have the same memory type - * - Only works for DDR2, DDR3 and DDR4 for now - * - Only works on systems with 1 to 4 memory slots + * - Only works for DDR, DDR2, DDR3 and DDR4 for now + * - Only works on systems with 1 to 8 memory slots */ #if IS_ENABLED(CONFIG_DMI) void i2c_register_spd(struct i2c_adapter *adap) @@ -354,9 +354,9 @@ void i2c_register_spd(struct i2c_adapter dev_info(&adap->dev, "%d/%d memory slots populated (from DMI)\n", dimm_count, slot_count); - if (slot_count > 4) { + if (slot_count > 8) { dev_warn(&adap->dev, - "Systems with more than 4 memory slots not supported yet, not instantiating SPD\n"); + "Systems with more than 8 memory slots not supported yet, not instantiating SPD\n"); return; }